<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2022 Workiva-->
<!--r:f832e964-5cde-408a-bffc-6b9222ecf3e2,g:9e560033-74c6-4bf1-8db2-93ab70cb868b-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.boozallen.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnaudited" xlink:type="simple" xlink:href="bah-20220930.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnaudited"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnaudited" xlink:type="extended" id="i77d1d43e9b5a4b928087a091781d3965_CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnaudited">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_96853e73-3f1f-4af3-b138-2ef8ae882d46" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_96853e73-3f1f-4af3-b138-2ef8ae882d46" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_132e12ba-e8fa-4614-b26f-59e3782d35e7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_132e12ba-e8fa-4614-b26f-59e3782d35e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_d696f7bb-c58b-4d09-a5f7-e69aa8fed0a3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_d696f7bb-c58b-4d09-a5f7-e69aa8fed0a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_073e70df-b5e9-4433-bee6-c86046fd1d30" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_TreasuryStockCommonShares_073e70df-b5e9-4433-bee6-c86046fd1d30" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_6150add4-9a45-481e-ae84-1cb71e7c71da" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_6150add4-9a45-481e-ae84-1cb71e7c71da" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_66724c32-3c75-4bb7-9cfa-9db977c3e974" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_66724c32-3c75-4bb7-9cfa-9db977c3e974" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_414413ba-7ea5-42fa-872a-1a45818c5b69" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_414413ba-7ea5-42fa-872a-1a45818c5b69" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_cec5a808-4ddd-4349-adbd-66beba2b2201" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_cec5a808-4ddd-4349-adbd-66beba2b2201" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_df6a9424-20eb-47fa-8d3b-a548425f2129" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_df6a9424-20eb-47fa-8d3b-a548425f2129" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_f1ed2f52-9e7a-4a95-9492-53369e5266f2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_f1ed2f52-9e7a-4a95-9492-53369e5266f2" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_AdjustmentsToAdditionalPaidInCapitalRecognitionOfLiabilityRelatedToFutureRestrictedStockUnitsVesting_cfce4969-6808-4846-bd7d-0b438ab08606" xlink:href="bah-20220930.xsd#bah_AdjustmentsToAdditionalPaidInCapitalRecognitionOfLiabilityRelatedToFutureRestrictedStockUnitsVesting"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_bah_AdjustmentsToAdditionalPaidInCapitalRecognitionOfLiabilityRelatedToFutureRestrictedStockUnitsVesting_cfce4969-6808-4846-bd7d-0b438ab08606" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_b0965614-87ff-44d0-af61-05b29fe32cd6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_ProfitLoss_b0965614-87ff-44d0-af61-05b29fe32cd6" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_779d9037-3a7a-40c6-8910-4ee80ffe9561" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_779d9037-3a7a-40c6-8910-4ee80ffe9561" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCash_9d05a2b7-0483-4b02-978e-0117536ea938" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DividendsCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_DividendsCash_9d05a2b7-0483-4b02-978e-0117536ea938" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_3ce39e49-d195-4e85-adb1-a21bccf10407" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_3ce39e49-d195-4e85-adb1-a21bccf10407" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_NoncontrollingInterestIncreaseFromContributions_a216bac6-61b1-4319-84f2-af10a8f7744b" xlink:href="bah-20220930.xsd#bah_NoncontrollingInterestIncreaseFromContributions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_80477947-869e-4678-84a2-a9d30c546544" xlink:to="loc_bah_NoncontrollingInterestIncreaseFromContributions_a216bac6-61b1-4319-84f2-af10a8f7744b" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_3e08dc0e-8a3b-4018-99d2-3c28be436055" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_4ab46ca9-f634-498c-9755-de7fcb94a903" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_fbb175ed-c1b7-4b55-8686-e122484caaf6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_dc876742-3be2-4214-a8e3-bbc7a806433f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_96853e73-3f1f-4af3-b138-2ef8ae882d46" xlink:to="loc_us-gaap_StatementTable_dc876742-3be2-4214-a8e3-bbc7a806433f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_2dacadad-69e1-45fa-a87b-4cfc87060c2f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_dc876742-3be2-4214-a8e3-bbc7a806433f" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_2dacadad-69e1-45fa-a87b-4cfc87060c2f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_2dacadad-69e1-45fa-a87b-4cfc87060c2f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_2dacadad-69e1-45fa-a87b-4cfc87060c2f" xlink:to="loc_us-gaap_EquityComponentDomain_2dacadad-69e1-45fa-a87b-4cfc87060c2f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_2dacadad-69e1-45fa-a87b-4cfc87060c2f" xlink:to="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_631de9c9-3938-4d8e-8a72-e6dcbddfe1f4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:to="loc_us-gaap_CommonStockMember_631de9c9-3938-4d8e-8a72-e6dcbddfe1f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_3f3ea9ca-2e96-4e38-a779-66fec9855866" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:to="loc_us-gaap_TreasuryStockCommonMember_3f3ea9ca-2e96-4e38-a779-66fec9855866" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_948b2603-a545-4a68-a157-4b2a4a3ac3be" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_948b2603-a545-4a68-a157-4b2a4a3ac3be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_bd4eff45-8054-4741-9440-0587b5b12c72" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:to="loc_us-gaap_RetainedEarningsMember_bd4eff45-8054-4741-9440-0587b5b12c72" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_f0905766-b04f-4315-a256-ce3af8cce661" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_f0905766-b04f-4315-a256-ce3af8cce661" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestMember_00a77371-4d35-4fa7-a30a-a09dca9b5343" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_NoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8cacb5f7-6bff-477e-94ef-083111aabd1b" xlink:to="loc_us-gaap_NoncontrollingInterestMember_00a77371-4d35-4fa7-a30a-a09dca9b5343" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_4a3a05e1-2f0b-4118-ae9e-efd49b620957" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_dc876742-3be2-4214-a8e3-bbc7a806433f" xlink:to="loc_us-gaap_StatementClassOfStockAxis_4a3a05e1-2f0b-4118-ae9e-efd49b620957" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_4a3a05e1-2f0b-4118-ae9e-efd49b620957_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_4a3a05e1-2f0b-4118-ae9e-efd49b620957" xlink:to="loc_us-gaap_ClassOfStockDomain_4a3a05e1-2f0b-4118-ae9e-efd49b620957_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_ff138d14-589b-4eff-940f-fd760f4e747e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_4a3a05e1-2f0b-4118-ae9e-efd49b620957" xlink:to="loc_us-gaap_ClassOfStockDomain_ff138d14-589b-4eff-940f-fd760f4e747e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_eadeac4e-cbd0-49d9-8207-68c6e4ff230f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_ff138d14-589b-4eff-940f-fd760f4e747e" xlink:to="loc_us-gaap_CommonClassAMember_eadeac4e-cbd0-49d9-8207-68c6e4ff230f" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnauditedParenthetical" xlink:type="simple" xlink:href="bah-20220930.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnauditedParenthetical"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnauditedParenthetical" xlink:type="extended" id="i6a672232fb444932b39ae369b3bd323d_CONDENSEDCONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUnauditedParenthetical">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_77a3dd74-9bdb-4179-bec7-dc80d86fd5f2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareCashPaid_c94b4df0-5f6f-4d9d-b56b-1886699cb903" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonStockDividendsPerShareCashPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_77a3dd74-9bdb-4179-bec7-dc80d86fd5f2" xlink:to="loc_us-gaap_CommonStockDividendsPerShareCashPaid_c94b4df0-5f6f-4d9d-b56b-1886699cb903" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_15b03f49-6454-4784-b460-1784a6338628" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_77a3dd74-9bdb-4179-bec7-dc80d86fd5f2" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_15b03f49-6454-4784-b460-1784a6338628" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_6f538dd9-454c-4f3f-a3f2-987ef77f385e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_77a3dd74-9bdb-4179-bec7-dc80d86fd5f2" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_6f538dd9-454c-4f3f-a3f2-987ef77f385e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_RepurchaseOfStockToSatisfyTaxWithholdingsRestrictedStockAmount_b9d5e6c1-daed-4957-9008-28fb7882d0bc" xlink:href="bah-20220930.xsd#bah_RepurchaseOfStockToSatisfyTaxWithholdingsRestrictedStockAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_77a3dd74-9bdb-4179-bec7-dc80d86fd5f2" xlink:to="loc_bah_RepurchaseOfStockToSatisfyTaxWithholdingsRestrictedStockAmount_b9d5e6c1-daed-4957-9008-28fb7882d0bc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_6758f5f3-2679-4eef-a629-7e2f39eb5f2d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_77a3dd74-9bdb-4179-bec7-dc80d86fd5f2" xlink:to="loc_us-gaap_StatementTable_6758f5f3-2679-4eef-a629-7e2f39eb5f2d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_4c91b5f0-975a-4498-a5b9-85872ec82c25" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_6758f5f3-2679-4eef-a629-7e2f39eb5f2d" xlink:to="loc_us-gaap_StatementClassOfStockAxis_4c91b5f0-975a-4498-a5b9-85872ec82c25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_4c91b5f0-975a-4498-a5b9-85872ec82c25_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_4c91b5f0-975a-4498-a5b9-85872ec82c25" xlink:to="loc_us-gaap_ClassOfStockDomain_4c91b5f0-975a-4498-a5b9-85872ec82c25_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_0cdc6b94-71e6-4e95-ab47-fb10de9a6fff" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_4c91b5f0-975a-4498-a5b9-85872ec82c25" xlink:to="loc_us-gaap_ClassOfStockDomain_0cdc6b94-71e6-4e95-ab47-fb10de9a6fff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_975b6110-271d-4c6d-93a9-2b4ffb6cd5b2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_0cdc6b94-71e6-4e95-ab47-fb10de9a6fff" xlink:to="loc_us-gaap_CommonClassAMember_975b6110-271d-4c6d-93a9-2b4ffb6cd5b2" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/REVENUEDisaggregationofRevenueDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#REVENUEDisaggregationofRevenueDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/REVENUEDisaggregationofRevenueDetails" xlink:type="extended" id="i6d0f0c7e94de4ad4908c5128a2f1eede_REVENUEDisaggregationofRevenueDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_c48c1958-f21e-4822-91fa-f73323fd7e2c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_1c06320f-c4f5-45f2-bfe5-89da9696e40c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_c48c1958-f21e-4822-91fa-f73323fd7e2c" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_1c06320f-c4f5-45f2-bfe5-89da9696e40c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_d66f6ce0-8cc5-402c-9ee9-fbdb35830329" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_c48c1958-f21e-4822-91fa-f73323fd7e2c" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_d66f6ce0-8cc5-402c-9ee9-fbdb35830329" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_c48c1958-f21e-4822-91fa-f73323fd7e2c" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_c403518a-0ec8-49df-9aae-52e9c4c88d74" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerBasisOfPricingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_c403518a-0ec8-49df-9aae-52e9c4c88d74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_c403518a-0ec8-49df-9aae-52e9c4c88d74_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_c403518a-0ec8-49df-9aae-52e9c4c88d74" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_c403518a-0ec8-49df-9aae-52e9c4c88d74_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_f042b54a-0cd7-4c4b-bb26-d43a5c7dea4f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_c403518a-0ec8-49df-9aae-52e9c4c88d74" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_f042b54a-0cd7-4c4b-bb26-d43a5c7dea4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_CostReimbursableContractMember_3c0db0c7-f23e-4029-bf9b-0d425e57c690" xlink:href="bah-20220930.xsd#bah_CostReimbursableContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_f042b54a-0cd7-4c4b-bb26-d43a5c7dea4f" xlink:to="loc_bah_CostReimbursableContractMember_3c0db0c7-f23e-4029-bf9b-0d425e57c690" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeAndMaterialsContractMember_ea18f983-eaf2-41ca-b5dd-52b6ab1c60d8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TimeAndMaterialsContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_f042b54a-0cd7-4c4b-bb26-d43a5c7dea4f" xlink:to="loc_us-gaap_TimeAndMaterialsContractMember_ea18f983-eaf2-41ca-b5dd-52b6ab1c60d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FixedPriceContractMember_74f2c57d-944f-4bfd-b8e4-eab809f466b8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FixedPriceContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_f042b54a-0cd7-4c4b-bb26-d43a5c7dea4f" xlink:to="loc_us-gaap_FixedPriceContractMember_74f2c57d-944f-4bfd-b8e4-eab809f466b8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_c3374447-c03f-4ae7-b1af-dd7c395d69b0" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:to="loc_srt_MajorCustomersAxis_c3374447-c03f-4ae7-b1af-dd7c395d69b0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_c3374447-c03f-4ae7-b1af-dd7c395d69b0_default" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_c3374447-c03f-4ae7-b1af-dd7c395d69b0" xlink:to="loc_srt_NameOfMajorCustomerDomain_c3374447-c03f-4ae7-b1af-dd7c395d69b0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_9d625142-19b1-490e-a5ee-4cc1d0532790" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_c3374447-c03f-4ae7-b1af-dd7c395d69b0" xlink:to="loc_srt_NameOfMajorCustomerDomain_9d625142-19b1-490e-a5ee-4cc1d0532790" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_DefenseClientsMember_be8999ff-fe06-4e2e-a546-706e82cc99eb" xlink:href="bah-20220930.xsd#bah_DefenseClientsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_9d625142-19b1-490e-a5ee-4cc1d0532790" xlink:to="loc_bah_DefenseClientsMember_be8999ff-fe06-4e2e-a546-706e82cc99eb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_IntelligenceClientsMember_ec7c19f8-9957-4173-aadb-6ae914833049" xlink:href="bah-20220930.xsd#bah_IntelligenceClientsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_9d625142-19b1-490e-a5ee-4cc1d0532790" xlink:to="loc_bah_IntelligenceClientsMember_ec7c19f8-9957-4173-aadb-6ae914833049" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_CivilClientsMember_0527f898-25c8-4299-8d9f-813d19032f22" xlink:href="bah-20220930.xsd#bah_CivilClientsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_9d625142-19b1-490e-a5ee-4cc1d0532790" xlink:to="loc_bah_CivilClientsMember_0527f898-25c8-4299-8d9f-813d19032f22" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_GlobalCommercialClientsMember_c00322bc-5975-4d35-8728-417f98d53a01" xlink:href="bah-20220930.xsd#bah_GlobalCommercialClientsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_9d625142-19b1-490e-a5ee-4cc1d0532790" xlink:to="loc_bah_GlobalCommercialClientsMember_c00322bc-5975-4d35-8728-417f98d53a01" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_58695354-f84e-484d-87c9-41639b7aa084" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:to="loc_srt_StatementGeographicalAxis_58695354-f84e-484d-87c9-41639b7aa084" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_58695354-f84e-484d-87c9-41639b7aa084_default" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_58695354-f84e-484d-87c9-41639b7aa084" xlink:to="loc_srt_SegmentGeographicalDomain_58695354-f84e-484d-87c9-41639b7aa084_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_649800d8-e43a-4d75-8e15-7376dad16d4d" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_58695354-f84e-484d-87c9-41639b7aa084" xlink:to="loc_srt_SegmentGeographicalDomain_649800d8-e43a-4d75-8e15-7376dad16d4d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_af334c8d-b112-44d3-8a8a-e7bcbbd6ac5c" xlink:href="https://xbrl.sec.gov/country/2022/country-2022.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_649800d8-e43a-4d75-8e15-7376dad16d4d" xlink:to="loc_country_US_af334c8d-b112-44d3-8a8a-e7bcbbd6ac5c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelAxis_af8f863e-b3b8-42f1-aad6-b9875a00c342" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerSalesChannelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelAxis_af8f863e-b3b8-42f1-aad6-b9875a00c342" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelDomain_af8f863e-b3b8-42f1-aad6-b9875a00c342_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerSalesChannelDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelAxis_af8f863e-b3b8-42f1-aad6-b9875a00c342" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelDomain_af8f863e-b3b8-42f1-aad6-b9875a00c342_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelDomain_33c65cd2-8feb-4294-a351-2a778f5f9589" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ContractWithCustomerSalesChannelDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelAxis_af8f863e-b3b8-42f1-aad6-b9875a00c342" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelDomain_33c65cd2-8feb-4294-a351-2a778f5f9589" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesChannelDirectlyToConsumerMember_9b7c4c98-5df9-448d-8ca8-00d69078f08b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SalesChannelDirectlyToConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelDomain_33c65cd2-8feb-4294-a351-2a778f5f9589" xlink:to="loc_us-gaap_SalesChannelDirectlyToConsumerMember_9b7c4c98-5df9-448d-8ca8-00d69078f08b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesChannelThroughIntermediaryMember_38b0d94a-db19-4cea-9be8-d130024d3d08" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SalesChannelThroughIntermediaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelDomain_33c65cd2-8feb-4294-a351-2a778f5f9589" xlink:to="loc_us-gaap_SalesChannelThroughIntermediaryMember_38b0d94a-db19-4cea-9be8-d130024d3d08" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_81c3c7c4-06a1-4dc0-91eb-f0133c07d88a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_81c3c7c4-06a1-4dc0-91eb-f0133c07d88a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_81c3c7c4-06a1-4dc0-91eb-f0133c07d88a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_81c3c7c4-06a1-4dc0-91eb-f0133c07d88a" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_81c3c7c4-06a1-4dc0-91eb-f0133c07d88a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_55c3e9d9-f406-481b-9b0a-6440dd54ad80" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_81c3c7c4-06a1-4dc0-91eb-f0133c07d88a" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_55c3e9d9-f406-481b-9b0a-6440dd54ad80" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember_a5a43586-b4ce-464a-b24f-8e6a51456f66" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueFromContractWithCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_55c3e9d9-f406-481b-9b0a-6440dd54ad80" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerMember_a5a43586-b4ce-464a-b24f-8e6a51456f66" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_9b3b8969-a7ae-4e1a-a04f-d254585f2abe" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a4a1222f-43c6-4c02-8b12-abe19f644363" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_9b3b8969-a7ae-4e1a-a04f-d254585f2abe" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_9b3b8969-a7ae-4e1a-a04f-d254585f2abe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_9b3b8969-a7ae-4e1a-a04f-d254585f2abe" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_9b3b8969-a7ae-4e1a-a04f-d254585f2abe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_9138d4f1-91ab-4600-af6c-394e33c83748" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_9b3b8969-a7ae-4e1a-a04f-d254585f2abe" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_9138d4f1-91ab-4600-af6c-394e33c83748" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductConcentrationRiskMember_5a5b4291-dd85-4889-ac79-1ec44c95a002" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ProductConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_9138d4f1-91ab-4600-af6c-394e33c83748" xlink:to="loc_us-gaap_ProductConcentrationRiskMember_5a5b4291-dd85-4889-ac79-1ec44c95a002" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_da6a4cd2-4769-442d-813b-da8a81f60e7b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_9138d4f1-91ab-4600-af6c-394e33c83748" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_da6a4cd2-4769-442d-813b-da8a81f60e7b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_ContractorConcentrationTypeRiskMember_ebc4fb53-88dd-4b8f-b4e7-8c1efee26774" xlink:href="bah-20220930.xsd#bah_ContractorConcentrationTypeRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_9138d4f1-91ab-4600-af6c-394e33c83748" xlink:to="loc_bah_ContractorConcentrationTypeRiskMember_ebc4fb53-88dd-4b8f-b4e7-8c1efee26774" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/REVENUENarrativeDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#REVENUENarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/REVENUENarrativeDetails" xlink:type="extended" id="i4b469de9684e4018a8e141cab5a0bc17_REVENUENarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_f5aa5e47-52f7-4372-9189-7936720aa4d4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_f5aa5e47-52f7-4372-9189-7936720aa4d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_41b88fc1-2d75-43a3-81b3-0d9492a91780" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_41b88fc1-2d75-43a3-81b3-0d9492a91780" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_77ebcfe5-4cae-40aa-8c3e-4d53c1eeac0d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_77ebcfe5-4cae-40aa-8c3e-4d53c1eeac0d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_a552c194-681b-40f1-9790-01947c036861" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_77ebcfe5-4cae-40aa-8c3e-4d53c1eeac0d" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_a552c194-681b-40f1-9790-01947c036861" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/REVENUENarrativeDetails_1" xlink:type="simple" xlink:href="bah-20220930.xsd#REVENUENarrativeDetails_1"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/REVENUENarrativeDetails_1" xlink:type="extended" id="i8ae3b8a6849f4488afa1ffe133593239_REVENUENarrativeDetails_1">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_f5aa5e47-52f7-4372-9189-7936720aa4d4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_f5aa5e47-52f7-4372-9189-7936720aa4d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_41b88fc1-2d75-43a3-81b3-0d9492a91780" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_41b88fc1-2d75-43a3-81b3-0d9492a91780" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_77ebcfe5-4cae-40aa-8c3e-4d53c1eeac0d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_d22b14af-c5c4-44d2-bfa2-ff670d492abd" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_77ebcfe5-4cae-40aa-8c3e-4d53c1eeac0d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/ACQUISITIONSDIVESTITURESANDGOODWILLDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#ACQUISITIONSDIVESTITURESANDGOODWILLDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/ACQUISITIONSDIVESTITURESANDGOODWILLDetails" xlink:type="extended" id="i55148f0c2d7d4afda2fcf818cc39868b_ACQUISITIONSDIVESTITURESANDGOODWILLDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_2fe74671-1f82-4951-bd6e-6c239c6fb367" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_6e99bdbb-fcc1-4f19-a4bb-c80b4221e8e4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_2fe74671-1f82-4951-bd6e-6c239c6fb367" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_6e99bdbb-fcc1-4f19-a4bb-c80b4221e8e4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_2f42c815-1208-4f7d-b5a8-7bcc0800ab6a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GainLossOnSaleOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_2fe74671-1f82-4951-bd6e-6c239c6fb367" xlink:to="loc_us-gaap_GainLossOnSaleOfBusiness_2f42c815-1208-4f7d-b5a8-7bcc0800ab6a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_81474c27-1a5b-4a59-9afd-e3519e2602e8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_2fe74671-1f82-4951-bd6e-6c239c6fb367" xlink:to="loc_us-gaap_Goodwill_81474c27-1a5b-4a59-9afd-e3519e2602e8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill1_34a41e6c-ab70-4935-bb88-4efba6536e05" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_2fe74671-1f82-4951-bd6e-6c239c6fb367" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill1_34a41e6c-ab70-4935-bb88-4efba6536e05" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_35c9dd09-cacc-4405-8302-f9ac6e6612a9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_2fe74671-1f82-4951-bd6e-6c239c6fb367" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_35c9dd09-cacc-4405-8302-f9ac6e6612a9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_193f9ac0-8561-4133-a812-0a73909edbce" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_35c9dd09-cacc-4405-8302-f9ac6e6612a9" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_193f9ac0-8561-4133-a812-0a73909edbce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_193f9ac0-8561-4133-a812-0a73909edbce_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_193f9ac0-8561-4133-a812-0a73909edbce" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_193f9ac0-8561-4133-a812-0a73909edbce_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_a917c398-563b-40bb-81a1-5fc93101c45f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_193f9ac0-8561-4133-a812-0a73909edbce" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_a917c398-563b-40bb-81a1-5fc93101c45f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_fd57c38e-db91-4005-83ad-ecc44bc05066" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_a917c398-563b-40bb-81a1-5fc93101c45f" xlink:to="loc_us-gaap_SubsequentEventMember_fd57c38e-db91-4005-83ad-ecc44bc05066" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_3e956299-e143-4983-84b8-c6b10e8d5940" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_35c9dd09-cacc-4405-8302-f9ac6e6612a9" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_3e956299-e143-4983-84b8-c6b10e8d5940" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_3e956299-e143-4983-84b8-c6b10e8d5940_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_3e956299-e143-4983-84b8-c6b10e8d5940" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_3e956299-e143-4983-84b8-c6b10e8d5940_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_314fa55d-7c9a-42b4-bdbe-df2c9e9b7564" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_3e956299-e143-4983-84b8-c6b10e8d5940" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_314fa55d-7c9a-42b4-bdbe-df2c9e9b7564" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_EverWatchMember_0cab82bc-3bdf-47a5-ada8-a59110ef4f24" xlink:href="bah-20220930.xsd#bah_EverWatchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_314fa55d-7c9a-42b4-bdbe-df2c9e9b7564" xlink:to="loc_bah_EverWatchMember_0cab82bc-3bdf-47a5-ada8-a59110ef4f24" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_bdef790f-5057-4717-ba94-1c2d4d2ba97f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_35c9dd09-cacc-4405-8302-f9ac6e6612a9" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_bdef790f-5057-4717-ba94-1c2d4d2ba97f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_bdef790f-5057-4717-ba94-1c2d4d2ba97f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_bdef790f-5057-4717-ba94-1c2d4d2ba97f" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_bdef790f-5057-4717-ba94-1c2d4d2ba97f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_00c9404d-4016-4b70-a453-63e39732bc8b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_bdef790f-5057-4717-ba94-1c2d4d2ba97f" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_00c9404d-4016-4b70-a453-63e39732bc8b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_MENABusinessMember_a39429b8-67a9-46c0-ad0c-8fbb39895789" xlink:href="bah-20220930.xsd#bah_MENABusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_00c9404d-4016-4b70-a453-63e39732bc8b" xlink:to="loc_bah_MENABusinessMember_a39429b8-67a9-46c0-ad0c-8fbb39895789" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_bd942199-dfa0-4863-90d0-6c98a5bbfe3a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_35c9dd09-cacc-4405-8302-f9ac6e6612a9" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_bd942199-dfa0-4863-90d0-6c98a5bbfe3a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_bd942199-dfa0-4863-90d0-6c98a5bbfe3a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_bd942199-dfa0-4863-90d0-6c98a5bbfe3a" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_bd942199-dfa0-4863-90d0-6c98a5bbfe3a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_12104b1b-6336-47f9-a845-353841049d51" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_bd942199-dfa0-4863-90d0-6c98a5bbfe3a" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_12104b1b-6336-47f9-a845-353841049d51" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_52602c71-b70c-46bc-bc3e-25d50a356a73" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_12104b1b-6336-47f9-a845-353841049d51" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_52602c71-b70c-46bc-bc3e-25d50a356a73" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/ACCOUNTSPAYABLEANDOTHERACCRUEDEXPENSESDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#ACCOUNTSPAYABLEANDOTHERACCRUEDEXPENSESDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/ACCOUNTSPAYABLEANDOTHERACCRUEDEXPENSESDetails" xlink:type="extended" id="i78975355fea140c7b62b423dcb372095_ACCOUNTSPAYABLEANDOTHERACCRUEDEXPENSESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_c5830546-eec6-436b-9631-87e8ab944fe8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyAccrualAtCarryingValue_4247d007-a14d-496b-95ef-16f62f567eb8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingencyAccrualAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_c5830546-eec6-436b-9631-87e8ab944fe8" xlink:to="loc_us-gaap_LossContingencyAccrualAtCarryingValue_4247d007-a14d-496b-95ef-16f62f567eb8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_e755ad41-8a43-4522-b9d0-91f012b8bd69" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_c5830546-eec6-436b-9631-87e8ab944fe8" xlink:to="loc_us-gaap_LossContingenciesTable_e755ad41-8a43-4522-b9d0-91f012b8bd69" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_9ec6ac23-b9c2-4b58-9ce0-afdfcd54d2ee" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_e755ad41-8a43-4522-b9d0-91f012b8bd69" xlink:to="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_9ec6ac23-b9c2-4b58-9ce0-afdfcd54d2ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyNatureDomain_9ec6ac23-b9c2-4b58-9ce0-afdfcd54d2ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_9ec6ac23-b9c2-4b58-9ce0-afdfcd54d2ee" xlink:to="loc_us-gaap_LossContingencyNatureDomain_9ec6ac23-b9c2-4b58-9ce0-afdfcd54d2ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyNatureDomain_33b7ed4c-710e-4c45-8294-9b49c26f54dc" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_9ec6ac23-b9c2-4b58-9ce0-afdfcd54d2ee" xlink:to="loc_us-gaap_LossContingencyNatureDomain_33b7ed4c-710e-4c45-8294-9b49c26f54dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnfavorableRegulatoryActionMember_eba3ebf3-afc2-487a-bf8e-437bc1732818" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_UnfavorableRegulatoryActionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_33b7ed4c-710e-4c45-8294-9b49c26f54dc" xlink:to="loc_us-gaap_UnfavorableRegulatoryActionMember_eba3ebf3-afc2-487a-bf8e-437bc1732818" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/DEBTScheduleofDebtDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#DEBTScheduleofDebtDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/DEBTScheduleofDebtDetails" xlink:type="extended" id="ic67d190672064d19aed9b55c9ec9ce2f_DEBTScheduleofDebtDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_d312e23c-8e98-4e91-a2fa-2865214bc04c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtCurrentAndNoncurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_d312e23c-8e98-4e91-a2fa-2865214bc04c" xlink:to="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_34559bc8-4200-4e13-8c5f-99bf2d2ae724" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_34559bc8-4200-4e13-8c5f-99bf2d2ae724" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_bb1132e4-94ee-42f5-825d-a445d1d3dba0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_bb1132e4-94ee-42f5-825d-a445d1d3dba0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_afdbc785-6993-4af3-825e-4810ed3d653a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_afdbc785-6993-4af3-825e-4810ed3d653a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_9872aa8f-b7a2-4aaa-962f-90d5a7dc00b2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:to="loc_us-gaap_LongTermDebt_9872aa8f-b7a2-4aaa-962f-90d5a7dc00b2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_4a17ba38-bf31-4d50-ae6b-a8762d95b0f9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:to="loc_us-gaap_LongTermDebtCurrent_4a17ba38-bf31-4d50-ae6b-a8762d95b0f9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_6856e0c2-dcb0-4303-b4ea-261a15d06214" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtCurrentAndNoncurrentAbstract_193a0e9c-f097-4848-ab5d-19450b810802" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_6856e0c2-dcb0-4303-b4ea-261a15d06214" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_388c1f9c-1ba1-4b33-ae01-9b7b0992bc2a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_d312e23c-8e98-4e91-a2fa-2865214bc04c" xlink:to="loc_us-gaap_DebtInstrumentTable_388c1f9c-1ba1-4b33-ae01-9b7b0992bc2a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_a737b75b-e667-40ee-811f-3016f27a4ff1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_388c1f9c-1ba1-4b33-ae01-9b7b0992bc2a" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_a737b75b-e667-40ee-811f-3016f27a4ff1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_a737b75b-e667-40ee-811f-3016f27a4ff1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_a737b75b-e667-40ee-811f-3016f27a4ff1" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_a737b75b-e667-40ee-811f-3016f27a4ff1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_8cfa50c4-59ec-4521-bf2b-f6bc4ecf2c9d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_a737b75b-e667-40ee-811f-3016f27a4ff1" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_8cfa50c4-59ec-4521-bf2b-f6bc4ecf2c9d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_30b3e164-8d71-4ca2-acb3-56ec5df0b1d3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_8cfa50c4-59ec-4521-bf2b-f6bc4ecf2c9d" xlink:to="loc_us-gaap_SecuredDebtMember_30b3e164-8d71-4ca2-acb3-56ec5df0b1d3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_b3185967-b59c-4360-a437-5f3280b21014" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_8cfa50c4-59ec-4521-bf2b-f6bc4ecf2c9d" xlink:to="loc_us-gaap_SeniorNotesMember_b3185967-b59c-4360-a437-5f3280b21014" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_fc2ae299-b650-4652-9dbc-559900315b2f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_388c1f9c-1ba1-4b33-ae01-9b7b0992bc2a" xlink:to="loc_us-gaap_DebtInstrumentAxis_fc2ae299-b650-4652-9dbc-559900315b2f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_fc2ae299-b650-4652-9dbc-559900315b2f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_fc2ae299-b650-4652-9dbc-559900315b2f" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_fc2ae299-b650-4652-9dbc-559900315b2f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_f44e0e04-ffb4-46d4-ab62-2465d9e900b7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_fc2ae299-b650-4652-9dbc-559900315b2f" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_f44e0e04-ffb4-46d4-ab62-2465d9e900b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_NewTrancheATermLoanMember_94241f32-7e5e-4ea2-bc69-491849836a87" xlink:href="bah-20220930.xsd#bah_NewTrancheATermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_f44e0e04-ffb4-46d4-ab62-2465d9e900b7" xlink:to="loc_bah_NewTrancheATermLoanMember_94241f32-7e5e-4ea2-bc69-491849836a87" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TrancheALoansMember_44adf4fb-debf-45c6-8343-8ecb10596548" xlink:href="bah-20220930.xsd#bah_TrancheALoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_f44e0e04-ffb4-46d4-ab62-2465d9e900b7" xlink:to="loc_bah_TrancheALoansMember_44adf4fb-debf-45c6-8343-8ecb10596548" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TrancheBLoansMember_5176c9e1-cc16-4f7f-96cd-a2df0a567188" xlink:href="bah-20220930.xsd#bah_TrancheBLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_f44e0e04-ffb4-46d4-ab62-2465d9e900b7" xlink:to="loc_bah_TrancheBLoansMember_5176c9e1-cc16-4f7f-96cd-a2df0a567188" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_SeniorNotesDue2028Member_dd1eac4d-e9cb-4040-95be-229d2208db89" xlink:href="bah-20220930.xsd#bah_SeniorNotesDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_f44e0e04-ffb4-46d4-ab62-2465d9e900b7" xlink:to="loc_bah_SeniorNotesDue2028Member_dd1eac4d-e9cb-4040-95be-229d2208db89" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_SeniorNotesDue2029Member_5db9da6f-2b5a-467c-9251-6a9d87085a89" xlink:href="bah-20220930.xsd#bah_SeniorNotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_f44e0e04-ffb4-46d4-ab62-2465d9e900b7" xlink:to="loc_bah_SeniorNotesDue2029Member_5db9da6f-2b5a-467c-9251-6a9d87085a89" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/DEBTNarrativeDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#DEBTNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/DEBTNarrativeDetails" xlink:type="extended" id="i9ed692041a734ef682d7ee64e2f85314_DEBTNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_fa5f6211-73fe-4eeb-825d-52f1bced94f2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_fa5f6211-73fe-4eeb-825d-52f1bced94f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_72ff8a75-4a96-4172-930c-98f803385645" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_LineOfCredit_72ff8a75-4a96-4172-930c-98f803385645" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_85a8b98a-525e-4f58-95f6-7225c0f1287b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_85a8b98a-525e-4f58-95f6-7225c0f1287b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_DebtInstrumentBasisSpreadOnVariableRateAdjustment_b2a22dd2-dc5b-444d-adb4-050cf7826d1f" xlink:href="bah-20220930.xsd#bah_DebtInstrumentBasisSpreadOnVariableRateAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_bah_DebtInstrumentBasisSpreadOnVariableRateAdjustment_b2a22dd2-dc5b-444d-adb4-050cf7826d1f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_DebtInstrumentBasisSpreadOnVariableRateFloor_f4e873de-091e-45a3-8a59-e622fb237c12" xlink:href="bah-20220930.xsd#bah_DebtInstrumentBasisSpreadOnVariableRateFloor"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_bah_DebtInstrumentBasisSpreadOnVariableRateFloor_f4e873de-091e-45a3-8a59-e622fb237c12" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_14de7aa2-1818-4f64-be65-f6393aee01cb" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_14de7aa2-1818-4f64-be65-f6393aee01cb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_40c15833-7678-4445-822a-50db21970c78" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LineOfCreditFacilityCommitmentFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_40c15833-7678-4445-822a-50db21970c78" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_df958f0a-a456-4106-a9f1-c07513bb58c3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DeferredFinanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_df958f0a-a456-4106-a9f1-c07513bb58c3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_d6fa7f17-86a8-4e2e-b5f8-b8eef1ccbc6d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_d6fa7f17-86a8-4e2e-b5f8-b8eef1ccbc6d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_b5435ecd-bbd9-418c-8880-ce31218d3234" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_DerivativeNotionalAmount_b5435ecd-bbd9-418c-8880-ce31218d3234" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_e2e527ce-492b-47f5-a8b4-8235c4a0bd0e" xlink:to="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_28bec968-0790-48cd-b3c8-041e400b73d1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_28bec968-0790-48cd-b3c8-041e400b73d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_28bec968-0790-48cd-b3c8-041e400b73d1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_28bec968-0790-48cd-b3c8-041e400b73d1" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_28bec968-0790-48cd-b3c8-041e400b73d1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_b365311b-4974-4cc3-b374-700208352e42" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_28bec968-0790-48cd-b3c8-041e400b73d1" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_b365311b-4974-4cc3-b374-700208352e42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_e40b56f5-7907-42f6-97d8-962433e80a5d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_b365311b-4974-4cc3-b374-700208352e42" xlink:to="loc_us-gaap_SecuredDebtMember_e40b56f5-7907-42f6-97d8-962433e80a5d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_7ee408dd-2063-4e72-b32d-cbdb67944773" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_b365311b-4974-4cc3-b374-700208352e42" xlink:to="loc_us-gaap_SeniorNotesMember_7ee408dd-2063-4e72-b32d-cbdb67944773" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_77a84db8-672e-4125-9e8e-18219d56348b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_DebtInstrumentAxis_77a84db8-672e-4125-9e8e-18219d56348b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_77a84db8-672e-4125-9e8e-18219d56348b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_77a84db8-672e-4125-9e8e-18219d56348b" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_77a84db8-672e-4125-9e8e-18219d56348b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_77a84db8-672e-4125-9e8e-18219d56348b" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_NewTrancheATermLoanMember_3523ab85-3d46-478a-bd78-21223ed50e76" xlink:href="bah-20220930.xsd#bah_NewTrancheATermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_NewTrancheATermLoanMember_3523ab85-3d46-478a-bd78-21223ed50e76" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_SecuredCreditFacilityMember_4fef6709-b184-4871-9fb8-257c025874ff" xlink:href="bah-20220930.xsd#bah_SecuredCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_SecuredCreditFacilityMember_4fef6709-b184-4871-9fb8-257c025874ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_NewRevolvingCommitmentsMember_60ccb867-dbab-4939-ad01-62674c57b34e" xlink:href="bah-20220930.xsd#bah_NewRevolvingCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_NewRevolvingCommitmentsMember_60ccb867-dbab-4939-ad01-62674c57b34e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TermLoanAMember_219bb243-98e1-438f-901e-ab2930a728a7" xlink:href="bah-20220930.xsd#bah_TermLoanAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_TermLoanAMember_219bb243-98e1-438f-901e-ab2930a728a7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TermLoanBMember_ba2711cd-fa7d-4d0e-bc7c-f997f24ec224" xlink:href="bah-20220930.xsd#bah_TermLoanBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_TermLoanBMember_ba2711cd-fa7d-4d0e-bc7c-f997f24ec224" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TrancheALoansMember_d8d0b098-a7d9-40a4-8faa-fd483a6d4e43" xlink:href="bah-20220930.xsd#bah_TrancheALoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_TrancheALoansMember_d8d0b098-a7d9-40a4-8faa-fd483a6d4e43" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_A400SeniorNotesDue2029Member_73278756-91fc-4e45-a4fa-c861ae0ebaf6" xlink:href="bah-20220930.xsd#bah_A400SeniorNotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_A400SeniorNotesDue2029Member_73278756-91fc-4e45-a4fa-c861ae0ebaf6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_SeniorNotesDue2028Member_0182b483-23ef-45aa-aef8-0e73a2145b0d" xlink:href="bah-20220930.xsd#bah_SeniorNotesDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_cc9414fc-77bb-4467-bedd-7870162c46e7" xlink:to="loc_bah_SeniorNotesDue2028Member_0182b483-23ef-45aa-aef8-0e73a2145b0d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_066c5c1b-a2e3-4a92-93a2-bdc2e82430ef" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_CreditFacilityAxis_066c5c1b-a2e3-4a92-93a2-bdc2e82430ef" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_066c5c1b-a2e3-4a92-93a2-bdc2e82430ef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_066c5c1b-a2e3-4a92-93a2-bdc2e82430ef" xlink:to="loc_us-gaap_CreditFacilityDomain_066c5c1b-a2e3-4a92-93a2-bdc2e82430ef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_5a63d914-d298-46ac-9b9b-236ac409ffc0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_066c5c1b-a2e3-4a92-93a2-bdc2e82430ef" xlink:to="loc_us-gaap_CreditFacilityDomain_5a63d914-d298-46ac-9b9b-236ac409ffc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_3194cf41-a0b6-43e4-9aeb-9f9e68a5819a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_5a63d914-d298-46ac-9b9b-236ac409ffc0" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_3194cf41-a0b6-43e4-9aeb-9f9e68a5819a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LetterOfCreditMember_38fa6b64-2126-408c-9762-4cbc80cb2c1f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LetterOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_5a63d914-d298-46ac-9b9b-236ac409ffc0" xlink:to="loc_us-gaap_LetterOfCreditMember_38fa6b64-2126-408c-9762-4cbc80cb2c1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TriggeringEventAxis_347d3733-4b0d-4638-9f68-8341d59f30e0" xlink:href="bah-20220930.xsd#bah_TriggeringEventAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_bah_TriggeringEventAxis_347d3733-4b0d-4638-9f68-8341d59f30e0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TriggeringEventDomain_347d3733-4b0d-4638-9f68-8341d59f30e0_default" xlink:href="bah-20220930.xsd#bah_TriggeringEventDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_bah_TriggeringEventAxis_347d3733-4b0d-4638-9f68-8341d59f30e0" xlink:to="loc_bah_TriggeringEventDomain_347d3733-4b0d-4638-9f68-8341d59f30e0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TriggeringEventDomain_6adb94fc-1879-44f6-9132-4d74a1ce0429" xlink:href="bah-20220930.xsd#bah_TriggeringEventDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_bah_TriggeringEventAxis_347d3733-4b0d-4638-9f68-8341d59f30e0" xlink:to="loc_bah_TriggeringEventDomain_6adb94fc-1879-44f6-9132-4d74a1ce0429" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_BeforeTwoYearAnniversaryMember_45c4218f-feff-497d-9c78-c9ea84c1426a" xlink:href="bah-20220930.xsd#bah_BeforeTwoYearAnniversaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bah_TriggeringEventDomain_6adb94fc-1879-44f6-9132-4d74a1ce0429" xlink:to="loc_bah_BeforeTwoYearAnniversaryMember_45c4218f-feff-497d-9c78-c9ea84c1426a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_AfterTwoYearButBeforeFiveYearAnniversaryMember_ae884c78-a98e-4fec-b50f-a4ed1e016ef1" xlink:href="bah-20220930.xsd#bah_AfterTwoYearButBeforeFiveYearAnniversaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bah_TriggeringEventDomain_6adb94fc-1879-44f6-9132-4d74a1ce0429" xlink:to="loc_bah_AfterTwoYearButBeforeFiveYearAnniversaryMember_ae884c78-a98e-4fec-b50f-a4ed1e016ef1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_26d58003-76d4-4728-90bf-c30345400b54" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_VariableRateAxis_26d58003-76d4-4728-90bf-c30345400b54" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_26d58003-76d4-4728-90bf-c30345400b54_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_26d58003-76d4-4728-90bf-c30345400b54" xlink:to="loc_us-gaap_VariableRateDomain_26d58003-76d4-4728-90bf-c30345400b54_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_07eea277-49ba-44f4-8e25-6982e76556aa" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_26d58003-76d4-4728-90bf-c30345400b54" xlink:to="loc_us-gaap_VariableRateDomain_07eea277-49ba-44f4-8e25-6982e76556aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_03242189-d5cd-4dd4-ab29-e0304b926d36" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_07eea277-49ba-44f4-8e25-6982e76556aa" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_03242189-d5cd-4dd4-ab29-e0304b926d36" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_OvernightFederalFundsRateMember_077d4388-61aa-4ba9-b4f9-7d13a447b790" xlink:href="bah-20220930.xsd#bah_OvernightFederalFundsRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_07eea277-49ba-44f4-8e25-6982e76556aa" xlink:to="loc_bah_OvernightFederalFundsRateMember_077d4388-61aa-4ba9-b4f9-7d13a447b790" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_ThreeMonthTermSecuredOvernightFinancingRateSOFROvernightIndexSwapRateMember_0a49301c-c6d6-4ca6-9b94-98f4d70f4ba6" xlink:href="bah-20220930.xsd#bah_ThreeMonthTermSecuredOvernightFinancingRateSOFROvernightIndexSwapRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_07eea277-49ba-44f4-8e25-6982e76556aa" xlink:to="loc_bah_ThreeMonthTermSecuredOvernightFinancingRateSOFROvernightIndexSwapRateMember_0a49301c-c6d6-4ca6-9b94-98f4d70f4ba6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BaseRateMember_08a83224-d4f2-436d-8f67-184247a0cfe1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BaseRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_07eea277-49ba-44f4-8e25-6982e76556aa" xlink:to="loc_us-gaap_BaseRateMember_08a83224-d4f2-436d-8f67-184247a0cfe1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_154a907d-f517-405a-9ed0-99a3b184ff49" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_srt_RangeAxis_154a907d-f517-405a-9ed0-99a3b184ff49" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_154a907d-f517-405a-9ed0-99a3b184ff49_default" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_154a907d-f517-405a-9ed0-99a3b184ff49" xlink:to="loc_srt_RangeMember_154a907d-f517-405a-9ed0-99a3b184ff49_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_d0fd1243-a86a-4abf-976b-2cb47bfcb259" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_154a907d-f517-405a-9ed0-99a3b184ff49" xlink:to="loc_srt_RangeMember_d0fd1243-a86a-4abf-976b-2cb47bfcb259" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_cfffcfd6-7fb0-42ce-b109-1e66b9b1b567" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d0fd1243-a86a-4abf-976b-2cb47bfcb259" xlink:to="loc_srt_MinimumMember_cfffcfd6-7fb0-42ce-b109-1e66b9b1b567" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_ba33e8a7-f7db-49b1-a114-cd505ceb52c7" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_d0fd1243-a86a-4abf-976b-2cb47bfcb259" xlink:to="loc_srt_MaximumMember_ba33e8a7-f7db-49b1-a114-cd505ceb52c7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dc76a074-fa13-4594-b3cc-272a2255e43b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dc76a074-fa13-4594-b3cc-272a2255e43b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_dc76a074-fa13-4594-b3cc-272a2255e43b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dc76a074-fa13-4594-b3cc-272a2255e43b" xlink:to="loc_us-gaap_RelatedPartyDomain_dc76a074-fa13-4594-b3cc-272a2255e43b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_7073a766-320c-4f80-9833-d4ea00a151ab" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_dc76a074-fa13-4594-b3cc-272a2255e43b" xlink:to="loc_us-gaap_RelatedPartyDomain_7073a766-320c-4f80-9833-d4ea00a151ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_ThirdPartyMember_10f21a5f-a870-4015-88a2-86b5f0202cd4" xlink:href="bah-20220930.xsd#bah_ThirdPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_7073a766-320c-4f80-9833-d4ea00a151ab" xlink:to="loc_bah_ThirdPartyMember_10f21a5f-a870-4015-88a2-86b5f0202cd4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_eab31c3f-b389-4b7c-ac44-735ee5a42790" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_eab31c3f-b389-4b7c-ac44-735ee5a42790" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_eab31c3f-b389-4b7c-ac44-735ee5a42790_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_eab31c3f-b389-4b7c-ac44-735ee5a42790" xlink:to="loc_us-gaap_HedgingRelationshipDomain_eab31c3f-b389-4b7c-ac44-735ee5a42790_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_610cdafb-aa77-44df-83c2-c9b74cf9dae3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_eab31c3f-b389-4b7c-ac44-735ee5a42790" xlink:to="loc_us-gaap_HedgingRelationshipDomain_610cdafb-aa77-44df-83c2-c9b74cf9dae3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_975dfaae-5bc2-4d77-8ed6-83d6eb336e3d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_610cdafb-aa77-44df-83c2-c9b74cf9dae3" xlink:to="loc_us-gaap_CashFlowHedgingMember_975dfaae-5bc2-4d77-8ed6-83d6eb336e3d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_043d6c30-0643-4fba-ae71-846b66930fa4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_HedgingDesignationAxis_043d6c30-0643-4fba-ae71-846b66930fa4" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_043d6c30-0643-4fba-ae71-846b66930fa4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_043d6c30-0643-4fba-ae71-846b66930fa4" xlink:to="loc_us-gaap_HedgingDesignationDomain_043d6c30-0643-4fba-ae71-846b66930fa4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_24761795-d677-4a22-afa1-b6721b9f0c1c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_043d6c30-0643-4fba-ae71-846b66930fa4" xlink:to="loc_us-gaap_HedgingDesignationDomain_24761795-d677-4a22-afa1-b6721b9f0c1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_efa84b6b-c441-44e8-995c-f7e64bce9ac4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_24761795-d677-4a22-afa1-b6721b9f0c1c" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_efa84b6b-c441-44e8-995c-f7e64bce9ac4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_dfa88c77-aefb-49d6-917b-b1e559c4a808" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_925753b3-7d34-494d-adcf-43e39d278f7c" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_dfa88c77-aefb-49d6-917b-b1e559c4a808" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_dfa88c77-aefb-49d6-917b-b1e559c4a808_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_dfa88c77-aefb-49d6-917b-b1e559c4a808" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_dfa88c77-aefb-49d6-917b-b1e559c4a808_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_fa37a5b4-11a2-460c-8c8b-8607ca1caee2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_dfa88c77-aefb-49d6-917b-b1e559c4a808" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_fa37a5b4-11a2-460c-8c8b-8607ca1caee2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_ec4a627b-0339-473e-a753-46a9645f26f5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_fa37a5b4-11a2-460c-8c8b-8607ca1caee2" xlink:to="loc_us-gaap_InterestRateSwapMember_ec4a627b-0339-473e-a753-46a9645f26f5" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/DEBTInterestPaymentDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#DEBTInterestPaymentDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/DEBTInterestPaymentDetails" xlink:type="extended" id="iad626250fa464aafa8023475b351603d_DEBTInterestPaymentDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_224bbcd6-2760-46c1-8720-4d2a34d21d33" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestPaid_9ab19f03-5271-4c92-9646-588dcba87f03" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_224bbcd6-2760-46c1-8720-4d2a34d21d33" xlink:to="loc_us-gaap_InterestPaid_9ab19f03-5271-4c92-9646-588dcba87f03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_3b24aba9-3b9d-4c39-8906-6c5578afc1f6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_224bbcd6-2760-46c1-8720-4d2a34d21d33" xlink:to="loc_us-gaap_DebtInstrumentTable_3b24aba9-3b9d-4c39-8906-6c5578afc1f6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_c27cde81-c90d-469f-acfb-5b31fcffceba" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_3b24aba9-3b9d-4c39-8906-6c5578afc1f6" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_c27cde81-c90d-469f-acfb-5b31fcffceba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_c27cde81-c90d-469f-acfb-5b31fcffceba_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_c27cde81-c90d-469f-acfb-5b31fcffceba" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_c27cde81-c90d-469f-acfb-5b31fcffceba_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_30339fd3-233e-4ae3-bf75-9c3f625df7f1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_c27cde81-c90d-469f-acfb-5b31fcffceba" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_30339fd3-233e-4ae3-bf75-9c3f625df7f1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_43744ce2-9825-4e89-a1c3-1a20e4cb0130" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_30339fd3-233e-4ae3-bf75-9c3f625df7f1" xlink:to="loc_us-gaap_SecuredDebtMember_43744ce2-9825-4e89-a1c3-1a20e4cb0130" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_83832dec-226c-4ce7-9364-56f700d2048d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_3b24aba9-3b9d-4c39-8906-6c5578afc1f6" xlink:to="loc_us-gaap_DebtInstrumentAxis_83832dec-226c-4ce7-9364-56f700d2048d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_83832dec-226c-4ce7-9364-56f700d2048d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_83832dec-226c-4ce7-9364-56f700d2048d" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_83832dec-226c-4ce7-9364-56f700d2048d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_b7d57d11-a47e-42a8-8ae8-78ce0dc5024d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_83832dec-226c-4ce7-9364-56f700d2048d" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_b7d57d11-a47e-42a8-8ae8-78ce0dc5024d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TermLoanAMember_dfebd00b-56ba-43ef-b083-1a62e52e5354" xlink:href="bah-20220930.xsd#bah_TermLoanAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_b7d57d11-a47e-42a8-8ae8-78ce0dc5024d" xlink:to="loc_bah_TermLoanAMember_dfebd00b-56ba-43ef-b083-1a62e52e5354" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TermLoanBMember_82064513-451d-4ee9-b4d2-9e299010c674" xlink:href="bah-20220930.xsd#bah_TermLoanBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_b7d57d11-a47e-42a8-8ae8-78ce0dc5024d" xlink:to="loc_bah_TermLoanBMember_82064513-451d-4ee9-b4d2-9e299010c674" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/DEBTInterestExpenseDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#DEBTInterestExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/DEBTInterestExpenseDetails" xlink:type="extended" id="i85e9d3311d4941309e5a9255be178e01_DEBTInterestExpenseDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_7c5c1810-862b-4faf-88af-4b7671e68844" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_6ec26319-1220-46c0-a142-e8f5670f015a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7c5c1810-862b-4faf-88af-4b7671e68844" xlink:to="loc_us-gaap_InterestExpenseDebt_6ec26319-1220-46c0-a142-e8f5670f015a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_c55440d4-c7f8-4cdb-8684-c5305bfe53a9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7c5c1810-862b-4faf-88af-4b7671e68844" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_c55440d4-c7f8-4cdb-8684-c5305bfe53a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_InterestExpenseDebtInterestSwap_acdabc48-b763-4749-b7b5-d524b0d66434" xlink:href="bah-20220930.xsd#bah_InterestExpenseDebtInterestSwap"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7c5c1810-862b-4faf-88af-4b7671e68844" xlink:to="loc_bah_InterestExpenseDebtInterestSwap_acdabc48-b763-4749-b7b5-d524b0d66434" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_InterestIncomeExpenseOther_0875c40a-d03c-4eb8-9a40-2ac66bdc8b98" xlink:href="bah-20220930.xsd#bah_InterestIncomeExpenseOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7c5c1810-862b-4faf-88af-4b7671e68844" xlink:to="loc_bah_InterestIncomeExpenseOther_0875c40a-d03c-4eb8-9a40-2ac66bdc8b98" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpense_7ba86f0e-f2b4-4819-acb1-89bcd471fa15" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7c5c1810-862b-4faf-88af-4b7671e68844" xlink:to="loc_us-gaap_InterestExpense_7ba86f0e-f2b4-4819-acb1-89bcd471fa15" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_561c3733-41c7-40c4-865f-f13c50685579" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_7c5c1810-862b-4faf-88af-4b7671e68844" xlink:to="loc_us-gaap_DebtInstrumentTable_561c3733-41c7-40c4-865f-f13c50685579" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_44ffd6c1-95a6-4b03-90f1-c50d8ae411aa" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_561c3733-41c7-40c4-865f-f13c50685579" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_44ffd6c1-95a6-4b03-90f1-c50d8ae411aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_44ffd6c1-95a6-4b03-90f1-c50d8ae411aa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_44ffd6c1-95a6-4b03-90f1-c50d8ae411aa" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_44ffd6c1-95a6-4b03-90f1-c50d8ae411aa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_e83e8825-fe30-467d-9d12-3d9bd351a561" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_44ffd6c1-95a6-4b03-90f1-c50d8ae411aa" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_e83e8825-fe30-467d-9d12-3d9bd351a561" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_8ae6ba97-95bc-41af-bbff-c41732d6c5af" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_e83e8825-fe30-467d-9d12-3d9bd351a561" xlink:to="loc_us-gaap_SecuredDebtMember_8ae6ba97-95bc-41af-bbff-c41732d6c5af" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_83ad7174-a17f-4609-9834-d2b8f9febb8a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_e83e8825-fe30-467d-9d12-3d9bd351a561" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_83ad7174-a17f-4609-9834-d2b8f9febb8a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_0d453734-36ef-486a-9634-6700a6346724" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_e83e8825-fe30-467d-9d12-3d9bd351a561" xlink:to="loc_us-gaap_SeniorNotesMember_0d453734-36ef-486a-9634-6700a6346724" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_3f3b354c-66c4-4895-8e37-b64ecd48a416" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_561c3733-41c7-40c4-865f-f13c50685579" xlink:to="loc_us-gaap_DebtInstrumentAxis_3f3b354c-66c4-4895-8e37-b64ecd48a416" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_3f3b354c-66c4-4895-8e37-b64ecd48a416_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_3f3b354c-66c4-4895-8e37-b64ecd48a416" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_3f3b354c-66c4-4895-8e37-b64ecd48a416_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_75c9f8be-7b39-4595-9029-15203274716f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_3f3b354c-66c4-4895-8e37-b64ecd48a416" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_75c9f8be-7b39-4595-9029-15203274716f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_NewTrancheATermLoanMember_a1ebb7a9-381d-42c1-a72f-bbb5bb35496d" xlink:href="bah-20220930.xsd#bah_NewTrancheATermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_75c9f8be-7b39-4595-9029-15203274716f" xlink:to="loc_bah_NewTrancheATermLoanMember_a1ebb7a9-381d-42c1-a72f-bbb5bb35496d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TermLoanAMember_ca76236b-b0fe-40af-b0b0-0dc08cd08356" xlink:href="bah-20220930.xsd#bah_TermLoanAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_75c9f8be-7b39-4595-9029-15203274716f" xlink:to="loc_bah_TermLoanAMember_ca76236b-b0fe-40af-b0b0-0dc08cd08356" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TermLoanBMember_cd02d723-aed6-4010-b638-0562dadb55b6" xlink:href="bah-20220930.xsd#bah_TermLoanBMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_75c9f8be-7b39-4595-9029-15203274716f" xlink:to="loc_bah_TermLoanBMember_cd02d723-aed6-4010-b638-0562dadb55b6" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/DERIVATIVESNarrativeDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#DERIVATIVESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/DERIVATIVESNarrativeDetails" xlink:type="extended" id="i239a7cea273748589965eed3a5904b38_DERIVATIVESNarrativeDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_6770a995-7795-4fb4-a2bd-9df67ed816d7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_79ce98c1-c0f0-42ee-9af3-f6e93e30947f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6770a995-7795-4fb4-a2bd-9df67ed816d7" xlink:to="loc_us-gaap_DerivativeNotionalAmount_79ce98c1-c0f0-42ee-9af3-f6e93e30947f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_ca8301c7-ca8a-42c2-81fe-64fe090c2129" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6770a995-7795-4fb4-a2bd-9df67ed816d7" xlink:to="loc_us-gaap_DerivativeAssets_ca8301c7-ca8a-42c2-81fe-64fe090c2129" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_fa5e8ccc-5286-484d-83d9-dcacba086a6b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6770a995-7795-4fb4-a2bd-9df67ed816d7" xlink:to="loc_us-gaap_DerivativeLiabilities_fa5e8ccc-5286-484d-83d9-dcacba086a6b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet_344343f3-d7fe-4d34-83ac-09e3748733b2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_6770a995-7795-4fb4-a2bd-9df67ed816d7" xlink:to="loc_us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet_344343f3-d7fe-4d34-83ac-09e3748733b2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_3253860e-80e2-4ae5-a261-f20005c394ee" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_6770a995-7795-4fb4-a2bd-9df67ed816d7" xlink:to="loc_us-gaap_DerivativeTable_3253860e-80e2-4ae5-a261-f20005c394ee" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_bff7cb38-3bf9-4049-83b9-f7b4e65c36f2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_3253860e-80e2-4ae5-a261-f20005c394ee" xlink:to="loc_us-gaap_HedgingDesignationAxis_bff7cb38-3bf9-4049-83b9-f7b4e65c36f2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_bff7cb38-3bf9-4049-83b9-f7b4e65c36f2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_bff7cb38-3bf9-4049-83b9-f7b4e65c36f2" xlink:to="loc_us-gaap_HedgingDesignationDomain_bff7cb38-3bf9-4049-83b9-f7b4e65c36f2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_fbb8e0a0-73b1-47eb-ac28-736ef8375f3f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_bff7cb38-3bf9-4049-83b9-f7b4e65c36f2" xlink:to="loc_us-gaap_HedgingDesignationDomain_fbb8e0a0-73b1-47eb-ac28-736ef8375f3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_458ddd37-7686-432a-bc8d-7afa60e27c30" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_fbb8e0a0-73b1-47eb-ac28-736ef8375f3f" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_458ddd37-7686-432a-bc8d-7afa60e27c30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_1d699e33-c060-4053-aa66-87e25870cf75" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_3253860e-80e2-4ae5-a261-f20005c394ee" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_1d699e33-c060-4053-aa66-87e25870cf75" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_1d699e33-c060-4053-aa66-87e25870cf75_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_1d699e33-c060-4053-aa66-87e25870cf75" xlink:to="loc_us-gaap_HedgingRelationshipDomain_1d699e33-c060-4053-aa66-87e25870cf75_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_528f9234-d295-49d4-9f98-81f803c373ae" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_1d699e33-c060-4053-aa66-87e25870cf75" xlink:to="loc_us-gaap_HedgingRelationshipDomain_528f9234-d295-49d4-9f98-81f803c373ae" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_c370b928-79b9-48de-b48c-c064774fab3e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_528f9234-d295-49d4-9f98-81f803c373ae" xlink:to="loc_us-gaap_CashFlowHedgingMember_c370b928-79b9-48de-b48c-c064774fab3e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_4c527ca3-bb41-4907-931c-1751f283f1ce" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BalanceSheetLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_3253860e-80e2-4ae5-a261-f20005c394ee" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_4c527ca3-bb41-4907-931c-1751f283f1ce" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_4c527ca3-bb41-4907-931c-1751f283f1ce_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_4c527ca3-bb41-4907-931c-1751f283f1ce" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_4c527ca3-bb41-4907-931c-1751f283f1ce_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_bdafd6aa-8e98-466d-ac61-d91be1bd699c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_4c527ca3-bb41-4907-931c-1751f283f1ce" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_bdafd6aa-8e98-466d-ac61-d91be1bd699c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCurrentAssetsMember_f98e3188-5bb7-461d-b84c-6d9bae94b4e0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherCurrentAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_bdafd6aa-8e98-466d-ac61-d91be1bd699c" xlink:to="loc_us-gaap_OtherCurrentAssetsMember_f98e3188-5bb7-461d-b84c-6d9bae94b4e0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoncurrentAssetsMember_7ac94d63-f51f-4793-908c-5e6b68bf9ae6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherNoncurrentAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_bdafd6aa-8e98-466d-ac61-d91be1bd699c" xlink:to="loc_us-gaap_OtherNoncurrentAssetsMember_7ac94d63-f51f-4793-908c-5e6b68bf9ae6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCurrentLiabilitiesMember_9c2c2102-e2e8-418b-8d9f-4e5c56344695" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherCurrentLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_bdafd6aa-8e98-466d-ac61-d91be1bd699c" xlink:to="loc_us-gaap_OtherCurrentLiabilitiesMember_9c2c2102-e2e8-418b-8d9f-4e5c56344695" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoncurrentLiabilitiesMember_f17064b8-8ccb-4d76-a1b6-0c738a571aa3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherNoncurrentLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_bdafd6aa-8e98-466d-ac61-d91be1bd699c" xlink:to="loc_us-gaap_OtherNoncurrentLiabilitiesMember_f17064b8-8ccb-4d76-a1b6-0c738a571aa3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_72781fac-da0c-41ba-9038-d7a80402b1e4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_3253860e-80e2-4ae5-a261-f20005c394ee" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_72781fac-da0c-41ba-9038-d7a80402b1e4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_72781fac-da0c-41ba-9038-d7a80402b1e4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_72781fac-da0c-41ba-9038-d7a80402b1e4" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_72781fac-da0c-41ba-9038-d7a80402b1e4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_76e10a04-b946-4465-ae24-b46c50e48cba" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_72781fac-da0c-41ba-9038-d7a80402b1e4" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_76e10a04-b946-4465-ae24-b46c50e48cba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_f03e19ba-5137-434d-b631-d8d26c8f359b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_76e10a04-b946-4465-ae24-b46c50e48cba" xlink:to="loc_us-gaap_InterestRateSwapMember_f03e19ba-5137-434d-b631-d8d26c8f359b" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/DERIVATIVESEffectofDerivativesonFinancialStatementsDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#DERIVATIVESEffectofDerivativesonFinancialStatementsDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/DERIVATIVESEffectofDerivativesonFinancialStatementsDetails" xlink:type="extended" id="i8314b5b89929491ea42dc9346b389e47_DERIVATIVESEffectofDerivativesonFinancialStatementsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_05529615-46cf-4254-a9eb-1603fef0299d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_d7b68fd8-3276-4d32-86cb-945bb676c3ac" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_05529615-46cf-4254-a9eb-1603fef0299d" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_d7b68fd8-3276-4d32-86cb-945bb676c3ac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet_fbfa41f2-b7dd-4f8c-910e-7c74914bbb53" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_05529615-46cf-4254-a9eb-1603fef0299d" xlink:to="loc_us-gaap_InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet_fbfa41f2-b7dd-4f8c-910e-7c74914bbb53" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_7a656265-b50d-4014-955b-068d343dfd76" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ReclassificationFromAociCurrentPeriodTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_05529615-46cf-4254-a9eb-1603fef0299d" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_7a656265-b50d-4014-955b-068d343dfd76" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_53855961-5976-46e6-9576-9c0849bda064" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_05529615-46cf-4254-a9eb-1603fef0299d" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_53855961-5976-46e6-9576-9c0849bda064" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_1bc4425d-491c-4728-8ad9-2dc6d1774443" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_53855961-5976-46e6-9576-9c0849bda064" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_1bc4425d-491c-4728-8ad9-2dc6d1774443" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_1bc4425d-491c-4728-8ad9-2dc6d1774443_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_1bc4425d-491c-4728-8ad9-2dc6d1774443" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_1bc4425d-491c-4728-8ad9-2dc6d1774443_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_9827f918-8346-4d2f-9c40-47c802ddae3f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_1bc4425d-491c-4728-8ad9-2dc6d1774443" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_9827f918-8346-4d2f-9c40-47c802ddae3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_b9e727e0-694d-4b5f-9e14-8b5715ddeb5b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9827f918-8346-4d2f-9c40-47c802ddae3f" xlink:to="loc_us-gaap_InterestRateSwapMember_b9e727e0-694d-4b5f-9e14-8b5715ddeb5b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_4527d54c-a138-4869-8716-89c96b92ca02" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_53855961-5976-46e6-9576-9c0849bda064" xlink:to="loc_us-gaap_HedgingDesignationAxis_4527d54c-a138-4869-8716-89c96b92ca02" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_4527d54c-a138-4869-8716-89c96b92ca02_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_4527d54c-a138-4869-8716-89c96b92ca02" xlink:to="loc_us-gaap_HedgingDesignationDomain_4527d54c-a138-4869-8716-89c96b92ca02_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_385a6fa6-8e2a-47ac-96e9-396a2036254a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_4527d54c-a138-4869-8716-89c96b92ca02" xlink:to="loc_us-gaap_HedgingDesignationDomain_385a6fa6-8e2a-47ac-96e9-396a2036254a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_8a4f135e-261d-42ea-9f15-3899da1c62a1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_385a6fa6-8e2a-47ac-96e9-396a2036254a" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_8a4f135e-261d-42ea-9f15-3899da1c62a1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_fa2b646c-8b54-408b-aa1f-08f67e0af535" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_53855961-5976-46e6-9576-9c0849bda064" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_fa2b646c-8b54-408b-aa1f-08f67e0af535" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_fa2b646c-8b54-408b-aa1f-08f67e0af535_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_fa2b646c-8b54-408b-aa1f-08f67e0af535" xlink:to="loc_us-gaap_HedgingRelationshipDomain_fa2b646c-8b54-408b-aa1f-08f67e0af535_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_e8fe5a78-96b1-4673-a8c3-a785e1e1b717" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_fa2b646c-8b54-408b-aa1f-08f67e0af535" xlink:to="loc_us-gaap_HedgingRelationshipDomain_e8fe5a78-96b1-4673-a8c3-a785e1e1b717" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_8ac3db2a-940f-40ef-b701-020e908e8af5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_e8fe5a78-96b1-4673-a8c3-a785e1e1b717" xlink:to="loc_us-gaap_CashFlowHedgingMember_8ac3db2a-940f-40ef-b701-020e908e8af5" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/INCOMETAXESDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#INCOMETAXESDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/INCOMETAXESDetails" xlink:type="extended" id="i95b1c8d4c28d4d11910d11cfcca7c472_INCOMETAXESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwardsLineItems_43c320e2-f769-403f-ac27-b37dd03eea7e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLossCarryforwardsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_b2ebb11d-3652-4063-b53b-29602d2672ec" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_43c320e2-f769-403f-ac27-b37dd03eea7e" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_b2ebb11d-3652-4063-b53b-29602d2672ec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExaminationEstimateOfPossibleLoss_85c8c3d0-5043-47a9-9416-eba8455ad869" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeTaxExaminationEstimateOfPossibleLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_43c320e2-f769-403f-ac27-b37dd03eea7e" xlink:to="loc_us-gaap_IncomeTaxExaminationEstimateOfPossibleLoss_85c8c3d0-5043-47a9-9416-eba8455ad869" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit_38b42354-c86c-4de2-abcd-d8f7f1e68ee1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_43c320e2-f769-403f-ac27-b37dd03eea7e" xlink:to="loc_us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit_38b42354-c86c-4de2-abcd-d8f7f1e68ee1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExaminationLiabilityRefundAdjustmentFromSettlementWithTaxingAuthority_583e02a7-da4d-43c8-94d3-b44852d0903b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeTaxExaminationLiabilityRefundAdjustmentFromSettlementWithTaxingAuthority"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_43c320e2-f769-403f-ac27-b37dd03eea7e" xlink:to="loc_us-gaap_IncomeTaxExaminationLiabilityRefundAdjustmentFromSettlementWithTaxingAuthority_583e02a7-da4d-43c8-94d3-b44852d0903b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesReceivable_1bc0aba7-1309-42ab-a29b-6fa766621114" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeTaxesReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_43c320e2-f769-403f-ac27-b37dd03eea7e" xlink:to="loc_us-gaap_IncomeTaxesReceivable_1bc0aba7-1309-42ab-a29b-6fa766621114" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwardsTable_820863ac-605d-4095-9512-4f11f976b597" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OperatingLossCarryforwardsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_43c320e2-f769-403f-ac27-b37dd03eea7e" xlink:to="loc_us-gaap_OperatingLossCarryforwardsTable_820863ac-605d-4095-9512-4f11f976b597" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodAxis_af464d1e-25c5-4951-8237-6b42fcaa310a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TaxPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_820863ac-605d-4095-9512-4f11f976b597" xlink:to="loc_us-gaap_TaxPeriodAxis_af464d1e-25c5-4951-8237-6b42fcaa310a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_af464d1e-25c5-4951-8237-6b42fcaa310a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxPeriodAxis_af464d1e-25c5-4951-8237-6b42fcaa310a" xlink:to="loc_us-gaap_TaxPeriodDomain_af464d1e-25c5-4951-8237-6b42fcaa310a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_6e4d319e-2103-4197-ba39-3d6979029d5b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxPeriodAxis_af464d1e-25c5-4951-8237-6b42fcaa310a" xlink:to="loc_us-gaap_TaxPeriodDomain_6e4d319e-2103-4197-ba39-3d6979029d5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TaxYears20132015Member_f31845fb-7e60-47f1-a4c7-a6ca77ff62bb" xlink:href="bah-20220930.xsd#bah_TaxYears20132015Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxPeriodDomain_6e4d319e-2103-4197-ba39-3d6979029d5b" xlink:to="loc_bah_TaxYears20132015Member_f31845fb-7e60-47f1-a4c7-a6ca77ff62bb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_8c5cf192-57a2-4bd0-9a9f-cb1ef1857475" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_820863ac-605d-4095-9512-4f11f976b597" xlink:to="loc_srt_RangeAxis_8c5cf192-57a2-4bd0-9a9f-cb1ef1857475" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_8c5cf192-57a2-4bd0-9a9f-cb1ef1857475_default" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_8c5cf192-57a2-4bd0-9a9f-cb1ef1857475" xlink:to="loc_srt_RangeMember_8c5cf192-57a2-4bd0-9a9f-cb1ef1857475_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_4f359e2b-1baf-4edd-ba3c-124de49fa0d2" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_8c5cf192-57a2-4bd0-9a9f-cb1ef1857475" xlink:to="loc_srt_RangeMember_4f359e2b-1baf-4edd-ba3c-124de49fa0d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_63d0b263-be0c-4bf1-bd04-445eda3fdef5" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_4f359e2b-1baf-4edd-ba3c-124de49fa0d2" xlink:to="loc_srt_MinimumMember_63d0b263-be0c-4bf1-bd04-445eda3fdef5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_d7ad1e47-9aa8-4bf9-b7cd-8c04acb2b76c" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_4f359e2b-1baf-4edd-ba3c-124de49fa0d2" xlink:to="loc_srt_MaximumMember_d7ad1e47-9aa8-4bf9-b7cd-8c04acb2b76c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_c8fd7a07-f393-407a-8101-a8920d118f85" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_820863ac-605d-4095-9512-4f11f976b597" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_c8fd7a07-f393-407a-8101-a8920d118f85" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_c8fd7a07-f393-407a-8101-a8920d118f85_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_c8fd7a07-f393-407a-8101-a8920d118f85" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_c8fd7a07-f393-407a-8101-a8920d118f85_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_4822c847-857b-4dc4-9e0d-af527244e2dd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_c8fd7a07-f393-407a-8101-a8920d118f85" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_4822c847-857b-4dc4-9e0d-af527244e2dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_23ff9ac9-bfc0-4a7d-8534-f5fb13dbbe1d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_4822c847-857b-4dc4-9e0d-af527244e2dd" xlink:to="loc_us-gaap_SubsequentEventMember_23ff9ac9-bfc0-4a7d-8534-f5fb13dbbe1d" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/EMPLOYEEBENEFITPLANSDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#EMPLOYEEBENEFITPLANSDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/EMPLOYEEBENEFITPLANSDetails" xlink:type="extended" id="i159505dbf4ca46458bcc918749ea5788_EMPLOYEEBENEFITPLANSDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_45843aab-f45f-44e8-8641-eaba9ee70432" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_8299cbc2-f066-4145-92bc-112e2a5e2a65" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_45843aab-f45f-44e8-8641-eaba9ee70432" xlink:to="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_8299cbc2-f066-4145-92bc-112e2a5e2a65" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanCostRecognized_882b271a-b06b-439f-b396-f5b1340a3ab4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DefinedContributionPlanCostRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_45843aab-f45f-44e8-8641-eaba9ee70432" xlink:to="loc_us-gaap_DefinedContributionPlanCostRecognized_882b271a-b06b-439f-b396-f5b1340a3ab4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_ceb31e69-efab-452b-8a3a-fb8ba7a874af" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DefinedBenefitPlanFundedStatusOfPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_45843aab-f45f-44e8-8641-eaba9ee70432" xlink:to="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_ceb31e69-efab-452b-8a3a-fb8ba7a874af" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_276e64ef-685f-4071-99de-08e0c504ec9d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_45843aab-f45f-44e8-8641-eaba9ee70432" xlink:to="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_276e64ef-685f-4071-99de-08e0c504ec9d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanNameAxis_5ffe5212-2de0-4472-b1fc-232ba8bd392c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetirementPlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_276e64ef-685f-4071-99de-08e0c504ec9d" xlink:to="loc_us-gaap_RetirementPlanNameAxis_5ffe5212-2de0-4472-b1fc-232ba8bd392c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanNameDomain_5ffe5212-2de0-4472-b1fc-232ba8bd392c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetirementPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanNameAxis_5ffe5212-2de0-4472-b1fc-232ba8bd392c" xlink:to="loc_us-gaap_RetirementPlanNameDomain_5ffe5212-2de0-4472-b1fc-232ba8bd392c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanNameDomain_9ae347c2-3f80-4bd8-b44d-bd4f334ac6b3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetirementPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanNameAxis_5ffe5212-2de0-4472-b1fc-232ba8bd392c" xlink:to="loc_us-gaap_RetirementPlanNameDomain_9ae347c2-3f80-4bd8-b44d-bd4f334ac6b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_OfficerMedicalPlanMember_bac9c8d9-959f-457a-b819-6f84df592efa" xlink:href="bah-20220930.xsd#bah_OfficerMedicalPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanNameDomain_9ae347c2-3f80-4bd8-b44d-bd4f334ac6b3" xlink:to="loc_bah_OfficerMedicalPlanMember_bac9c8d9-959f-457a-b819-6f84df592efa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_14a231b5-663e-4f45-9106-28faa1b54c29" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetirementPlanTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_276e64ef-685f-4071-99de-08e0c504ec9d" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_14a231b5-663e-4f45-9106-28faa1b54c29" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_14a231b5-663e-4f45-9106-28faa1b54c29_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_14a231b5-663e-4f45-9106-28faa1b54c29" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_14a231b5-663e-4f45-9106-28faa1b54c29_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_57cf8ec6-c557-4a7f-9331-db06e98a8643" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_14a231b5-663e-4f45-9106-28faa1b54c29" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_57cf8ec6-c557-4a7f-9331-db06e98a8643" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_30ca569f-d882-425a-8769-5c7100e97eb6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_57cf8ec6-c557-4a7f-9331-db06e98a8643" xlink:to="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_30ca569f-d882-425a-8769-5c7100e97eb6" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSDetails" xlink:type="extended" id="ia92d527340b147749e1655bbdae63cf8_ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_e835924f-6d08-47e1-a525-2a487aa8de1a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_7e60d274-e785-4d9d-a0c6-37e90258c7c8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_e835924f-6d08-47e1-a525-2a487aa8de1a" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_7e60d274-e785-4d9d-a0c6-37e90258c7c8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_bcdc36cd-20b9-4150-a2a3-21312f1b1fee" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_7e60d274-e785-4d9d-a0c6-37e90258c7c8" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_bcdc36cd-20b9-4150-a2a3-21312f1b1fee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_32abbcdd-3ac1-4341-a84c-04ec23a483dd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_7e60d274-e785-4d9d-a0c6-37e90258c7c8" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_32abbcdd-3ac1-4341-a84c-04ec23a483dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_68eb6b62-ebbf-480d-ac97-5093dcec8535" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_7e60d274-e785-4d9d-a0c6-37e90258c7c8" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_68eb6b62-ebbf-480d-ac97-5093dcec8535" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_c1a31fe4-c045-4b55-bf7a-369756471701" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTaxAbstract_7e60d274-e785-4d9d-a0c6-37e90258c7c8" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_c1a31fe4-c045-4b55-bf7a-369756471701" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_1eaf313c-cab1-4937-9d3c-fbaff1a897e2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_08764390-4bcb-4638-bdde-0a8c37515fff" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_e835924f-6d08-47e1-a525-2a487aa8de1a" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_08764390-4bcb-4638-bdde-0a8c37515fff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_ca808788-50e5-48af-bbee-df4c0e694547" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_e835924f-6d08-47e1-a525-2a487aa8de1a" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_ca808788-50e5-48af-bbee-df4c0e694547" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_648d9581-4b56-4e43-b34c-ea829db78bc1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_ca808788-50e5-48af-bbee-df4c0e694547" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_648d9581-4b56-4e43-b34c-ea829db78bc1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_648d9581-4b56-4e43-b34c-ea829db78bc1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_648d9581-4b56-4e43-b34c-ea829db78bc1" xlink:to="loc_us-gaap_EquityComponentDomain_648d9581-4b56-4e43-b34c-ea829db78bc1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_9571b714-c071-45b7-b1f0-724ccdf17e25" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_648d9581-4b56-4e43-b34c-ea829db78bc1" xlink:to="loc_us-gaap_EquityComponentDomain_9571b714-c071-45b7-b1f0-724ccdf17e25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_9c2f9f5d-02d5-4f47-a438-1bc16597da19" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_9571b714-c071-45b7-b1f0-724ccdf17e25" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_9c2f9f5d-02d5-4f47-a438-1bc16597da19" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_b8da2be8-7af0-418c-8f74-0a650b19efd0" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_9c2f9f5d-02d5-4f47-a438-1bc16597da19" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_b8da2be8-7af0-418c-8f74-0a650b19efd0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_75d60f3f-7d8b-44a5-ab59-f8c73b35108e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_9c2f9f5d-02d5-4f47-a438-1bc16597da19" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_75d60f3f-7d8b-44a5-ab59-f8c73b35108e" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/STOCKBASEDCOMPENSATIONScheduleofStockbasedCompensationExpenseDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#STOCKBASEDCOMPENSATIONScheduleofStockbasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/STOCKBASEDCOMPENSATIONScheduleofStockbasedCompensationExpenseDetails" xlink:type="extended" id="if14375ab513b43afafbaf97474cc141c_STOCKBASEDCOMPENSATIONScheduleofStockbasedCompensationExpenseDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_3f679f54-a447-4f65-810b-11c0620d7815" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_cbd44aab-bd0c-425d-8556-6d63fdbda039" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_3f679f54-a447-4f65-810b-11c0620d7815" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_cbd44aab-bd0c-425d-8556-6d63fdbda039" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_f213e576-3222-4990-8e51-a2fa3c1baa92" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_3f679f54-a447-4f65-810b-11c0620d7815" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_f213e576-3222-4990-8e51-a2fa3c1baa92" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_5885929a-b6d0-42da-8841-644921cdd5bf" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_f213e576-3222-4990-8e51-a2fa3c1baa92" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_5885929a-b6d0-42da-8841-644921cdd5bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_5885929a-b6d0-42da-8841-644921cdd5bf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_5885929a-b6d0-42da-8841-644921cdd5bf" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_5885929a-b6d0-42da-8841-644921cdd5bf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_1337826a-2a62-41e2-894b-29cca07e1eb6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_5885929a-b6d0-42da-8841-644921cdd5bf" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_1337826a-2a62-41e2-894b-29cca07e1eb6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfSalesMember_4ab99539-7269-4eda-be98-5f0cdbba595f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CostOfSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_1337826a-2a62-41e2-894b-29cca07e1eb6" xlink:to="loc_us-gaap_CostOfSalesMember_4ab99539-7269-4eda-be98-5f0cdbba595f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_092b8fa2-138f-4002-b64e-5c8a38af54da" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_1337826a-2a62-41e2-894b-29cca07e1eb6" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_092b8fa2-138f-4002-b64e-5c8a38af54da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_eb4ebfaa-c65d-4ab2-afcd-c81d16035c8d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_f213e576-3222-4990-8e51-a2fa3c1baa92" xlink:to="loc_us-gaap_AwardTypeAxis_eb4ebfaa-c65d-4ab2-afcd-c81d16035c8d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_eb4ebfaa-c65d-4ab2-afcd-c81d16035c8d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_eb4ebfaa-c65d-4ab2-afcd-c81d16035c8d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_eb4ebfaa-c65d-4ab2-afcd-c81d16035c8d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b7dafa8c-7de5-4aec-9bac-5758a70bf959" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_eb4ebfaa-c65d-4ab2-afcd-c81d16035c8d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b7dafa8c-7de5-4aec-9bac-5758a70bf959" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_fb248ceb-db07-471b-9df0-1283865815c5" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b7dafa8c-7de5-4aec-9bac-5758a70bf959" xlink:to="loc_us-gaap_EmployeeStockOptionMember_fb248ceb-db07-471b-9df0-1283865815c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_0af34d23-f48b-4437-9f54-ddfc5b7897ab" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b7dafa8c-7de5-4aec-9bac-5758a70bf959" xlink:to="loc_us-gaap_RestrictedStockMember_0af34d23-f48b-4437-9f54-ddfc5b7897ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_de458ef2-d973-4047-b3ae-a05e5d4efabe" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_f213e576-3222-4990-8e51-a2fa3c1baa92" xlink:to="loc_us-gaap_PlanNameAxis_de458ef2-d973-4047-b3ae-a05e5d4efabe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_de458ef2-d973-4047-b3ae-a05e5d4efabe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_de458ef2-d973-4047-b3ae-a05e5d4efabe" xlink:to="loc_us-gaap_PlanNameDomain_de458ef2-d973-4047-b3ae-a05e5d4efabe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_b1c965f0-1483-4d99-b0d8-8966d3fd620b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_de458ef2-d973-4047-b3ae-a05e5d4efabe" xlink:to="loc_us-gaap_PlanNameDomain_b1c965f0-1483-4d99-b0d8-8966d3fd620b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_AmendedAndRestatedEquityIncentivePlanMember_3e976cce-afaf-4bd2-9e31-44819cf8d874" xlink:href="bah-20220930.xsd#bah_AmendedAndRestatedEquityIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_b1c965f0-1483-4d99-b0d8-8966d3fd620b" xlink:to="loc_bah_AmendedAndRestatedEquityIncentivePlanMember_3e976cce-afaf-4bd2-9e31-44819cf8d874" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_AnnualIncentivePlanMember_400a9f9f-a98a-4187-b1a9-46a5235f6bc5" xlink:href="bah-20220930.xsd#bah_AnnualIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_b1c965f0-1483-4d99-b0d8-8966d3fd620b" xlink:to="loc_bah_AnnualIncentivePlanMember_400a9f9f-a98a-4187-b1a9-46a5235f6bc5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_6fe1ee88-d8c1-4421-b256-1ad615b1fa9c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_f213e576-3222-4990-8e51-a2fa3c1baa92" xlink:to="loc_us-gaap_StatementClassOfStockAxis_6fe1ee88-d8c1-4421-b256-1ad615b1fa9c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_6fe1ee88-d8c1-4421-b256-1ad615b1fa9c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_6fe1ee88-d8c1-4421-b256-1ad615b1fa9c" xlink:to="loc_us-gaap_ClassOfStockDomain_6fe1ee88-d8c1-4421-b256-1ad615b1fa9c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_f6583ca3-d92b-4127-b4e8-db4f535e6409" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_6fe1ee88-d8c1-4421-b256-1ad615b1fa9c" xlink:to="loc_us-gaap_ClassOfStockDomain_f6583ca3-d92b-4127-b4e8-db4f535e6409" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_5a55d72a-a62f-4771-bb68-e73f8ea44f6c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_f6583ca3-d92b-4127-b4e8-db4f535e6409" xlink:to="loc_us-gaap_CommonClassAMember_5a55d72a-a62f-4771-bb68-e73f8ea44f6c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/STOCKBASEDCOMPENSATIONUnrecognizedCompensationDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#STOCKBASEDCOMPENSATIONUnrecognizedCompensationDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/STOCKBASEDCOMPENSATIONUnrecognizedCompensationDetails" xlink:type="extended" id="ib423009a1bbd427480983dd6d3c4d829_STOCKBASEDCOMPENSATIONUnrecognizedCompensationDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_309bd608-df6f-481d-b7c4-5fdb4578af03" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_4d4e0cf6-e002-45eb-b748-cd6fd48d9d33" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_309bd608-df6f-481d-b7c4-5fdb4578af03" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_4d4e0cf6-e002-45eb-b748-cd6fd48d9d33" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_e5340292-bc46-41da-bbcd-2bda57625941" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_309bd608-df6f-481d-b7c4-5fdb4578af03" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_e5340292-bc46-41da-bbcd-2bda57625941" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3f911a20-9b84-4880-a411-19e83029651d" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_309bd608-df6f-481d-b7c4-5fdb4578af03" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3f911a20-9b84-4880-a411-19e83029651d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_21128554-0e1c-41bc-95ee-8616e417b9bd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3f911a20-9b84-4880-a411-19e83029651d" xlink:to="loc_us-gaap_PlanNameAxis_21128554-0e1c-41bc-95ee-8616e417b9bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_21128554-0e1c-41bc-95ee-8616e417b9bd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_21128554-0e1c-41bc-95ee-8616e417b9bd" xlink:to="loc_us-gaap_PlanNameDomain_21128554-0e1c-41bc-95ee-8616e417b9bd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_7bba9972-c2c0-4922-b88c-0d06d2388941" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_21128554-0e1c-41bc-95ee-8616e417b9bd" xlink:to="loc_us-gaap_PlanNameDomain_7bba9972-c2c0-4922-b88c-0d06d2388941" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_AmendedAndRestatedEquityIncentivePlanMember_d73197db-def0-4f6e-b5b5-a864d0085472" xlink:href="bah-20220930.xsd#bah_AmendedAndRestatedEquityIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_7bba9972-c2c0-4922-b88c-0d06d2388941" xlink:to="loc_bah_AmendedAndRestatedEquityIncentivePlanMember_d73197db-def0-4f6e-b5b5-a864d0085472" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_AnnualIncentivePlanMember_9e1483d2-91de-4141-9b64-bfbae3dc6b72" xlink:href="bah-20220930.xsd#bah_AnnualIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_7bba9972-c2c0-4922-b88c-0d06d2388941" xlink:to="loc_bah_AnnualIncentivePlanMember_9e1483d2-91de-4141-9b64-bfbae3dc6b72" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_d0370d36-a41c-4398-9678-fddd3bc5b5c3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3f911a20-9b84-4880-a411-19e83029651d" xlink:to="loc_us-gaap_AwardTypeAxis_d0370d36-a41c-4398-9678-fddd3bc5b5c3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d0370d36-a41c-4398-9678-fddd3bc5b5c3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_d0370d36-a41c-4398-9678-fddd3bc5b5c3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_d0370d36-a41c-4398-9678-fddd3bc5b5c3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b9e1bc56-9a47-4dce-b721-f30ad5cb80bb" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_d0370d36-a41c-4398-9678-fddd3bc5b5c3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b9e1bc56-9a47-4dce-b721-f30ad5cb80bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_71b4a70d-5c75-4c20-b281-cb60b4c9c7f4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b9e1bc56-9a47-4dce-b721-f30ad5cb80bb" xlink:to="loc_us-gaap_EmployeeStockOptionMember_71b4a70d-5c75-4c20-b281-cb60b4c9c7f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember_2a184183-1958-4a25-a079-d577f05bcbdd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_b9e1bc56-9a47-4dce-b721-f30ad5cb80bb" xlink:to="loc_us-gaap_RestrictedStockMember_2a184183-1958-4a25-a079-d577f05bcbdd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_4fea1a1f-2842-4bfa-95cc-d414d5526f5c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_3f911a20-9b84-4880-a411-19e83029651d" xlink:to="loc_us-gaap_StatementClassOfStockAxis_4fea1a1f-2842-4bfa-95cc-d414d5526f5c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_4fea1a1f-2842-4bfa-95cc-d414d5526f5c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_4fea1a1f-2842-4bfa-95cc-d414d5526f5c" xlink:to="loc_us-gaap_ClassOfStockDomain_4fea1a1f-2842-4bfa-95cc-d414d5526f5c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_92bb75b3-9ad6-45fc-8068-dd8b208e14ee" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_4fea1a1f-2842-4bfa-95cc-d414d5526f5c" xlink:to="loc_us-gaap_ClassOfStockDomain_92bb75b3-9ad6-45fc-8068-dd8b208e14ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_24383c75-4c4e-4527-86e6-fbbb5b1b7233" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_92bb75b3-9ad6-45fc-8068-dd8b208e14ee" xlink:to="loc_us-gaap_CommonClassAMember_24383c75-4c4e-4527-86e6-fbbb5b1b7233" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/STOCKBASEDCOMPENSATIONEquityIncentivePlanDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#STOCKBASEDCOMPENSATIONEquityIncentivePlanDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/STOCKBASEDCOMPENSATIONEquityIncentivePlanDetails" xlink:type="extended" id="i13e699f423cb460a93fbf17532c68338_STOCKBASEDCOMPENSATIONEquityIncentivePlanDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2c46abb0-8289-423d-8eea-6566232d162b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_93e6393f-d55c-444d-8ebb-76244843870e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2c46abb0-8289-423d-8eea-6566232d162b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_93e6393f-d55c-444d-8ebb-76244843870e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_33b69f50-83aa-4676-90b0-774e3886d6e8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2c46abb0-8289-423d-8eea-6566232d162b" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_33b69f50-83aa-4676-90b0-774e3886d6e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_ba4e1d74-e42b-4e40-a1c3-fb9daed06a1f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2c46abb0-8289-423d-8eea-6566232d162b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_ba4e1d74-e42b-4e40-a1c3-fb9daed06a1f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross_faecafab-87ab-4579-bd8c-9252840b0c9e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2c46abb0-8289-423d-8eea-6566232d162b" xlink:to="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross_faecafab-87ab-4579-bd8c-9252840b0c9e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d71443d0-a7ab-43e8-906d-f06b9c5ddbe6" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_2c46abb0-8289-423d-8eea-6566232d162b" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d71443d0-a7ab-43e8-906d-f06b9c5ddbe6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_6e056225-11ec-4e18-9a72-a808a766973f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d71443d0-a7ab-43e8-906d-f06b9c5ddbe6" xlink:to="loc_us-gaap_PlanNameAxis_6e056225-11ec-4e18-9a72-a808a766973f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_6e056225-11ec-4e18-9a72-a808a766973f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_6e056225-11ec-4e18-9a72-a808a766973f" xlink:to="loc_us-gaap_PlanNameDomain_6e056225-11ec-4e18-9a72-a808a766973f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_34a55a8f-db88-4220-a1b4-8be26659fc74" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_6e056225-11ec-4e18-9a72-a808a766973f" xlink:to="loc_us-gaap_PlanNameDomain_34a55a8f-db88-4220-a1b4-8be26659fc74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_AmendedAndRestatedEquityIncentivePlanMember_7feecf68-3aeb-4d4d-bda9-4fd62d16a4f1" xlink:href="bah-20220930.xsd#bah_AmendedAndRestatedEquityIncentivePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_34a55a8f-db88-4220-a1b4-8be26659fc74" xlink:to="loc_bah_AmendedAndRestatedEquityIncentivePlanMember_7feecf68-3aeb-4d4d-bda9-4fd62d16a4f1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_bbf5f28d-a4fd-464e-a8c5-3603281be513" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_d71443d0-a7ab-43e8-906d-f06b9c5ddbe6" xlink:to="loc_us-gaap_AwardTypeAxis_bbf5f28d-a4fd-464e-a8c5-3603281be513" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bbf5f28d-a4fd-464e-a8c5-3603281be513_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_bbf5f28d-a4fd-464e-a8c5-3603281be513" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_bbf5f28d-a4fd-464e-a8c5-3603281be513_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_aba86e54-853d-444c-8cef-756a72b8d838" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_bbf5f28d-a4fd-464e-a8c5-3603281be513" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_aba86e54-853d-444c-8cef-756a72b8d838" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_ad3aa90e-cf3c-4411-bd45-6a80af67c8c4" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_aba86e54-853d-444c-8cef-756a72b8d838" xlink:to="loc_us-gaap_EmployeeStockOptionMember_ad3aa90e-cf3c-4411-bd45-6a80af67c8c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_65da3a16-5d28-4043-a52d-2a4bb5400c8f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_aba86e54-853d-444c-8cef-756a72b8d838" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_65da3a16-5d28-4043-a52d-2a4bb5400c8f" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/FAIRVALUEMEASUREMENTSRecurringFairValueMeasurementsDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#FAIRVALUEMEASUREMENTSRecurringFairValueMeasurementsDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/FAIRVALUEMEASUREMENTSRecurringFairValueMeasurementsDetails" xlink:type="extended" id="i0974a4ae73fd47aea13fc29f80d26498_FAIRVALUEMEASUREMENTSRecurringFairValueMeasurementsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fa30e05e-f28c-477c-9dfa-ed0102c688fe" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_60a221fa-51f5-426c-9375-994c261ba0a3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fa30e05e-f28c-477c-9dfa-ed0102c688fe" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_60a221fa-51f5-426c-9375-994c261ba0a3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_e20b4fbc-8ede-4be4-9f19-9b29db46bea3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_60a221fa-51f5-426c-9375-994c261ba0a3" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_e20b4fbc-8ede-4be4-9f19-9b29db46bea3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationPlanAssets_db1b85f3-eda5-41e2-bb87-722e38edb574" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DeferredCompensationPlanAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_60a221fa-51f5-426c-9375-994c261ba0a3" xlink:to="loc_us-gaap_DeferredCompensationPlanAssets_db1b85f3-eda5-41e2-bb87-722e38edb574" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsNoncurrent_398aa547-0924-4b5b-b7b7-9f7e564b1254" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_60a221fa-51f5-426c-9375-994c261ba0a3" xlink:to="loc_us-gaap_DerivativeAssetsNoncurrent_398aa547-0924-4b5b-b7b7-9f7e564b1254" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsFairValueDisclosure_b1a78752-6fff-4a1c-b8e8-f86131133d97" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_OtherAssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_60a221fa-51f5-426c-9375-994c261ba0a3" xlink:to="loc_us-gaap_OtherAssetsFairValueDisclosure_b1a78752-6fff-4a1c-b8e8-f86131133d97" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_db4e13f9-a49a-4876-813d-77e52c23e382" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fa30e05e-f28c-477c-9dfa-ed0102c688fe" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_db4e13f9-a49a-4876-813d-77e52c23e382" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilitiesCurrent_a52f6078-9930-43a9-87e8-a60e983e14a9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_db4e13f9-a49a-4876-813d-77e52c23e382" xlink:to="loc_us-gaap_DerivativeLiabilitiesCurrent_a52f6078-9930-43a9-87e8-a60e983e14a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilitiesNoncurrent_a87fae34-544e-4659-8ae5-abcfcd30123a" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DerivativeLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_db4e13f9-a49a-4876-813d-77e52c23e382" xlink:to="loc_us-gaap_DerivativeLiabilitiesNoncurrent_a87fae34-544e-4659-8ae5-abcfcd30123a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_34962b55-8b12-4136-af75-a872bc0387b9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_db4e13f9-a49a-4876-813d-77e52c23e382" xlink:to="loc_us-gaap_DeferredCompensationLiabilityClassifiedNoncurrent_34962b55-8b12-4136-af75-a872bc0387b9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialLiabilitiesFairValueDisclosure_6b86e57b-f304-4600-a69b-0cdc10581f64" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FinancialLiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_db4e13f9-a49a-4876-813d-77e52c23e382" xlink:to="loc_us-gaap_FinancialLiabilitiesFairValueDisclosure_6b86e57b-f304-4600-a69b-0cdc10581f64" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_d466ac15-c2be-4ae4-bfaf-b726ae4f9e8c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_fa30e05e-f28c-477c-9dfa-ed0102c688fe" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_d466ac15-c2be-4ae4-bfaf-b726ae4f9e8c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_0976383a-2718-453d-a640-6aa6d3bb851b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_d466ac15-c2be-4ae4-bfaf-b726ae4f9e8c" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_0976383a-2718-453d-a640-6aa6d3bb851b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_0976383a-2718-453d-a640-6aa6d3bb851b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_0976383a-2718-453d-a640-6aa6d3bb851b" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_0976383a-2718-453d-a640-6aa6d3bb851b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_8e30efd6-0c4c-4249-855f-3bf34d404f35" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_0976383a-2718-453d-a640-6aa6d3bb851b" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_8e30efd6-0c4c-4249-855f-3bf34d404f35" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_23def6ec-afbb-4220-acc7-b8463fa7db72" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_8e30efd6-0c4c-4249-855f-3bf34d404f35" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_23def6ec-afbb-4220-acc7-b8463fa7db72" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d67c4bed-1bee-4146-8b25-c33d1d502e85" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_d466ac15-c2be-4ae4-bfaf-b726ae4f9e8c" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d67c4bed-1bee-4146-8b25-c33d1d502e85" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_d67c4bed-1bee-4146-8b25-c33d1d502e85_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d67c4bed-1bee-4146-8b25-c33d1d502e85" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_d67c4bed-1bee-4146-8b25-c33d1d502e85_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_c4095463-a419-44eb-a301-3a29d000b989" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_d67c4bed-1bee-4146-8b25-c33d1d502e85" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_c4095463-a419-44eb-a301-3a29d000b989" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_49f3be30-bbab-40b0-a8e4-baf2bbd0b68e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_c4095463-a419-44eb-a301-3a29d000b989" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_49f3be30-bbab-40b0-a8e4-baf2bbd0b68e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_aa76b238-e7de-481c-aab1-e06f618660e3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_c4095463-a419-44eb-a301-3a29d000b989" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_aa76b238-e7de-481c-aab1-e06f618660e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_5d397bb0-60fe-4b5d-95d5-e63a112a3ce3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_c4095463-a419-44eb-a301-3a29d000b989" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_5d397bb0-60fe-4b5d-95d5-e63a112a3ce3" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/FAIRVALUEDISCLOSURESCarryingAmountsofNotesPayableDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#FAIRVALUEDISCLOSURESCarryingAmountsofNotesPayableDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/FAIRVALUEDISCLOSURESCarryingAmountsofNotesPayableDetails" xlink:type="extended" id="i3b34338266f54d919caae68c5116fff8_FAIRVALUEDISCLOSURESCarryingAmountsofNotesPayableDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_0ad793a6-b0c5-4174-8468-d8aacebbfe27" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_7f21bc63-b55f-47d9-914f-0479336ffe33" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_0ad793a6-b0c5-4174-8468-d8aacebbfe27" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_7f21bc63-b55f-47d9-914f-0479336ffe33" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue_dc90a5f1-ad76-4d61-94f2-988ffd2bb8bd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_0ad793a6-b0c5-4174-8468-d8aacebbfe27" xlink:to="loc_us-gaap_DebtInstrumentFairValue_dc90a5f1-ad76-4d61-94f2-988ffd2bb8bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTable_4480076e-d2ad-487a-8f66-de53a2800d76" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueByBalanceSheetGroupingTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_0ad793a6-b0c5-4174-8468-d8aacebbfe27" xlink:to="loc_us-gaap_FairValueByBalanceSheetGroupingTable_4480076e-d2ad-487a-8f66-de53a2800d76" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_b9852fdc-72fb-406d-a112-e0251cd7d5bf" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_4480076e-d2ad-487a-8f66-de53a2800d76" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_b9852fdc-72fb-406d-a112-e0251cd7d5bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_b9852fdc-72fb-406d-a112-e0251cd7d5bf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_b9852fdc-72fb-406d-a112-e0251cd7d5bf" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_b9852fdc-72fb-406d-a112-e0251cd7d5bf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_a096d147-5229-4cff-8096-837821763922" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_b9852fdc-72fb-406d-a112-e0251cd7d5bf" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_a096d147-5229-4cff-8096-837821763922" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_b8e4695a-ddb0-4585-aa3f-3ae9b0158000" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_a096d147-5229-4cff-8096-837821763922" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_b8e4695a-ddb0-4585-aa3f-3ae9b0158000" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_c77b5d2b-780b-46f7-beb9-6d6296aede6e" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_b8e4695a-ddb0-4585-aa3f-3ae9b0158000" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_c77b5d2b-780b-46f7-beb9-6d6296aede6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_ac369c17-5097-43ee-bd12-f2e8d32e80d1" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_b8e4695a-ddb0-4585-aa3f-3ae9b0158000" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_ac369c17-5097-43ee-bd12-f2e8d32e80d1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_d35ff6c1-fa4b-4f78-af5a-ec8bd842c6c8" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_4480076e-d2ad-487a-8f66-de53a2800d76" xlink:to="loc_us-gaap_DebtInstrumentAxis_d35ff6c1-fa4b-4f78-af5a-ec8bd842c6c8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_d35ff6c1-fa4b-4f78-af5a-ec8bd842c6c8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_d35ff6c1-fa4b-4f78-af5a-ec8bd842c6c8" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_d35ff6c1-fa4b-4f78-af5a-ec8bd842c6c8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_b305f472-3104-4bc1-9d4e-2631a49bf93f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_d35ff6c1-fa4b-4f78-af5a-ec8bd842c6c8" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_b305f472-3104-4bc1-9d4e-2631a49bf93f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_NewTrancheATermLoanMember_256628a7-4872-49bd-89df-6a74a83f26ee" xlink:href="bah-20220930.xsd#bah_NewTrancheATermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_b305f472-3104-4bc1-9d4e-2631a49bf93f" xlink:to="loc_bah_NewTrancheATermLoanMember_256628a7-4872-49bd-89df-6a74a83f26ee" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TrancheALoansMember_9ebe53b1-66a4-4fb6-87b7-555f5aa77f5b" xlink:href="bah-20220930.xsd#bah_TrancheALoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_b305f472-3104-4bc1-9d4e-2631a49bf93f" xlink:to="loc_bah_TrancheALoansMember_9ebe53b1-66a4-4fb6-87b7-555f5aa77f5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_TrancheBLoansMember_92b47536-ebff-45dc-964e-7b417a62e8a3" xlink:href="bah-20220930.xsd#bah_TrancheBLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_b305f472-3104-4bc1-9d4e-2631a49bf93f" xlink:to="loc_bah_TrancheBLoansMember_92b47536-ebff-45dc-964e-7b417a62e8a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_A388SeniorNotesDue2028Member_380ae402-dbad-4cc6-95f1-4450aab2f845" xlink:href="bah-20220930.xsd#bah_A388SeniorNotesDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_b305f472-3104-4bc1-9d4e-2631a49bf93f" xlink:to="loc_bah_A388SeniorNotesDue2028Member_380ae402-dbad-4cc6-95f1-4450aab2f845" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_A400SeniorNotesDue2029Member_e7c18b84-22e2-4d8a-9616-13157057e2d5" xlink:href="bah-20220930.xsd#bah_A400SeniorNotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_b305f472-3104-4bc1-9d4e-2631a49bf93f" xlink:to="loc_bah_A400SeniorNotesDue2029Member_e7c18b84-22e2-4d8a-9616-13157057e2d5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_7bf84908-ffd7-4319-ad29-efda9e1e6c5c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_4480076e-d2ad-487a-8f66-de53a2800d76" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_7bf84908-ffd7-4319-ad29-efda9e1e6c5c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_7bf84908-ffd7-4319-ad29-efda9e1e6c5c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_7bf84908-ffd7-4319-ad29-efda9e1e6c5c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_7bf84908-ffd7-4319-ad29-efda9e1e6c5c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_3361fa34-d7ca-48d6-9ab3-b5ae20ac8dea" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_7bf84908-ffd7-4319-ad29-efda9e1e6c5c" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_3361fa34-d7ca-48d6-9ab3-b5ae20ac8dea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_a476811e-d381-4aef-b370-541959a02ddc" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3361fa34-d7ca-48d6-9ab3-b5ae20ac8dea" xlink:to="loc_us-gaap_SecuredDebtMember_a476811e-d381-4aef-b370-541959a02ddc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_78874c3e-98b3-4b88-b436-8d8d3768f6a9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_3361fa34-d7ca-48d6-9ab3-b5ae20ac8dea" xlink:to="loc_us-gaap_SeniorNotesMember_78874c3e-98b3-4b88-b436-8d8d3768f6a9" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/COMMITMENTSANDCONTINGENCIESDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#COMMITMENTSANDCONTINGENCIESDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/COMMITMENTSANDCONTINGENCIESDetails" xlink:type="extended" id="i158872861af94378b4135b40a07765fe_COMMITMENTSANDCONTINGENCIESDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskLineItems_6db3a493-6783-43c8-a090-dcce41d709a3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_aa5fd8cb-813d-4f01-873f-91c355c4be55" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GuaranteeObligationsCurrentCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_6db3a493-6783-43c8-a090-dcce41d709a3" xlink:to="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_aa5fd8cb-813d-4f01-873f-91c355c4be55" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsLiquidationProceeds_b150507f-4840-4c9d-af0c-1684b0323490" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GuaranteeObligationsLiquidationProceeds"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_6db3a493-6783-43c8-a090-dcce41d709a3" xlink:to="loc_us-gaap_GuaranteeObligationsLiquidationProceeds_b150507f-4840-4c9d-af0c-1684b0323490" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_GuarantorObligationsFacility_fbf03b9c-d6e2-4a37-b58e-7de2de0fc2c9" xlink:href="bah-20220930.xsd#bah_GuarantorObligationsFacility"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_6db3a493-6783-43c8-a090-dcce41d709a3" xlink:to="loc_bah_GuarantorObligationsFacility_fbf03b9c-d6e2-4a37-b58e-7de2de0fc2c9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_GuarantorObligationsAvailableAmount_f54f17f6-3a58-4379-8b60-afad3a989089" xlink:href="bah-20220930.xsd#bah_GuarantorObligationsAvailableAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_6db3a493-6783-43c8-a090-dcce41d709a3" xlink:to="loc_bah_GuarantorObligationsAvailableAmount_f54f17f6-3a58-4379-8b60-afad3a989089" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_72d28ef7-66a2-4f72-a74d-37932344f373" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_6db3a493-6783-43c8-a090-dcce41d709a3" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_72d28ef7-66a2-4f72-a74d-37932344f373" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTable_eb1e804b-7baa-48af-a9b8-f3b2741c79ca" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_6db3a493-6783-43c8-a090-dcce41d709a3" xlink:to="loc_us-gaap_ConcentrationRiskTable_eb1e804b-7baa-48af-a9b8-f3b2741c79ca" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsByNatureAxis_1fc0de8f-25b9-4c83-8ff4-a394a100acc3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GuaranteeObligationsByNatureAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_eb1e804b-7baa-48af-a9b8-f3b2741c79ca" xlink:to="loc_us-gaap_GuaranteeObligationsByNatureAxis_1fc0de8f-25b9-4c83-8ff4-a394a100acc3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_1fc0de8f-25b9-4c83-8ff4-a394a100acc3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_1fc0de8f-25b9-4c83-8ff4-a394a100acc3" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_1fc0de8f-25b9-4c83-8ff4-a394a100acc3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_9d014adc-ab72-4da0-b366-d4e19f82a089" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_1fc0de8f-25b9-4c83-8ff4-a394a100acc3" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_9d014adc-ab72-4da0-b366-d4e19f82a089" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialStandbyLetterOfCreditMember_dbe277ab-881a-4c26-8a7f-8a0192402670" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_FinancialStandbyLetterOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsNatureDomain_9d014adc-ab72-4da0-b366-d4e19f82a089" xlink:to="loc_us-gaap_FinancialStandbyLetterOfCreditMember_dbe277ab-881a-4c26-8a7f-8a0192402670" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_269386ab-c639-4707-8177-61353f12f27c" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_eb1e804b-7baa-48af-a9b8-f3b2741c79ca" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_269386ab-c639-4707-8177-61353f12f27c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_269386ab-c639-4707-8177-61353f12f27c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_269386ab-c639-4707-8177-61353f12f27c" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_269386ab-c639-4707-8177-61353f12f27c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_3d19c628-f8de-4425-9b3e-95217b6a626b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_269386ab-c639-4707-8177-61353f12f27c" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_3d19c628-f8de-4425-9b3e-95217b6a626b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GovernmentContractsConcentrationRiskMember_64197a2a-cc4a-4361-84b4-437c3fffaa34" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_GovernmentContractsConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_3d19c628-f8de-4425-9b3e-95217b6a626b" xlink:to="loc_us-gaap_GovernmentContractsConcentrationRiskMember_64197a2a-cc4a-4361-84b4-437c3fffaa34" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_ddb0f881-d9c8-4917-bba5-a4358de5c715" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_eb1e804b-7baa-48af-a9b8-f3b2741c79ca" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_ddb0f881-d9c8-4917-bba5-a4358de5c715" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_ddb0f881-d9c8-4917-bba5-a4358de5c715_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_ddb0f881-d9c8-4917-bba5-a4358de5c715" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_ddb0f881-d9c8-4917-bba5-a4358de5c715_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_7fee6db1-7d20-4f97-b97a-249d69379cf7" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_ddb0f881-d9c8-4917-bba5-a4358de5c715" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_7fee6db1-7d20-4f97-b97a-249d69379cf7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesRevenueNetMember_6646cb54-1b8f-4242-9754-90b1a0515ebb" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SalesRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_7fee6db1-7d20-4f97-b97a-249d69379cf7" xlink:to="loc_us-gaap_SalesRevenueNetMember_6646cb54-1b8f-4242-9754-90b1a0515ebb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_9d77d54b-5bac-461e-a276-2d8acaefb7a8" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ConcentrationRiskTable_eb1e804b-7baa-48af-a9b8-f3b2741c79ca" xlink:to="loc_srt_StatementGeographicalAxis_9d77d54b-5bac-461e-a276-2d8acaefb7a8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_9d77d54b-5bac-461e-a276-2d8acaefb7a8_default" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_9d77d54b-5bac-461e-a276-2d8acaefb7a8" xlink:to="loc_srt_SegmentGeographicalDomain_9d77d54b-5bac-461e-a276-2d8acaefb7a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_9cce80e1-19b6-42bb-adfb-cc1c518d239b" xlink:href="https://xbrl.fasb.org/srt/2022/elts/srt-2022.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_9d77d54b-5bac-461e-a276-2d8acaefb7a8" xlink:to="loc_srt_SegmentGeographicalDomain_9cce80e1-19b6-42bb-adfb-cc1c518d239b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_485068b5-5657-4e99-9d45-be27fe917569" xlink:href="https://xbrl.sec.gov/country/2022/country-2022.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_9cce80e1-19b6-42bb-adfb-cc1c518d239b" xlink:to="loc_country_US_485068b5-5657-4e99-9d45-be27fe917569" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_2d80f22c-1de8-488f-a0f8-d7d51b68c51b" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyAccrualAtCarryingValue_cdd5380f-af7d-443f-af01-15b6f43638f2" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingencyAccrualAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_2d80f22c-1de8-488f-a0f8-d7d51b68c51b" xlink:to="loc_us-gaap_LossContingencyAccrualAtCarryingValue_cdd5380f-af7d-443f-af01-15b6f43638f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_ddc27936-1eb0-4e9c-a0d3-cfb7db91c083" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_2d80f22c-1de8-488f-a0f8-d7d51b68c51b" xlink:to="loc_us-gaap_LossContingenciesTable_ddc27936-1eb0-4e9c-a0d3-cfb7db91c083" xlink:type="arc" order="2" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_ede3ac36-6675-4b9c-9fb6-dd12cf955bd9" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_ddc27936-1eb0-4e9c-a0d3-cfb7db91c083" xlink:to="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_ede3ac36-6675-4b9c-9fb6-dd12cf955bd9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyNatureDomain_ede3ac36-6675-4b9c-9fb6-dd12cf955bd9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_ede3ac36-6675-4b9c-9fb6-dd12cf955bd9" xlink:to="loc_us-gaap_LossContingencyNatureDomain_ede3ac36-6675-4b9c-9fb6-dd12cf955bd9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyNatureDomain_917dc482-242e-4d70-b7ee-73c0ae2d3ebd" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_LossContingencyNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_ede3ac36-6675-4b9c-9fb6-dd12cf955bd9" xlink:to="loc_us-gaap_LossContingencyNatureDomain_917dc482-242e-4d70-b7ee-73c0ae2d3ebd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnfavorableRegulatoryActionMember_6013a2f9-869a-459e-bfff-092cc1a340c3" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_UnfavorableRegulatoryActionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_917dc482-242e-4d70-b7ee-73c0ae2d3ebd" xlink:to="loc_us-gaap_UnfavorableRegulatoryActionMember_6013a2f9-869a-459e-bfff-092cc1a340c3" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.boozallen.com/role/SUBSEQUENTEVENTDetails" xlink:type="simple" xlink:href="bah-20220930.xsd#SUBSEQUENTEVENTDetails"/>
  <link:definitionLink xlink:role="http://www.boozallen.com/role/SUBSEQUENTEVENTDetails" xlink:type="extended" id="i0bb37818b4e04efaaa39d95fdb4b7437_SUBSEQUENTEVENTDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_e0f28e41-cb1e-4902-899a-a2eb6ad6a573" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_2d485948-8c1c-4501-9ce7-710af4300b7f" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_e0f28e41-cb1e-4902-899a-a2eb6ad6a573" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_2d485948-8c1c-4501-9ce7-710af4300b7f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_48dfaa3d-0fe0-4ca5-8841-3bbe2d627292" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_e0f28e41-cb1e-4902-899a-a2eb6ad6a573" xlink:to="loc_us-gaap_SubsequentEventTable_48dfaa3d-0fe0-4ca5-8841-3bbe2d627292" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_4115a4bc-0fa2-494f-b93e-2bd49d2f4690" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_48dfaa3d-0fe0-4ca5-8841-3bbe2d627292" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_4115a4bc-0fa2-494f-b93e-2bd49d2f4690" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_4115a4bc-0fa2-494f-b93e-2bd49d2f4690_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_4115a4bc-0fa2-494f-b93e-2bd49d2f4690" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_4115a4bc-0fa2-494f-b93e-2bd49d2f4690_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_3bc5ae0d-f23e-4e61-9da5-d3bb8fd91d93" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_4115a4bc-0fa2-494f-b93e-2bd49d2f4690" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_3bc5ae0d-f23e-4e61-9da5-d3bb8fd91d93" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_8bad8e44-5de1-43c5-95a7-873bed6c5d34" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_3bc5ae0d-f23e-4e61-9da5-d3bb8fd91d93" xlink:to="loc_us-gaap_SubsequentEventMember_8bad8e44-5de1-43c5-95a7-873bed6c5d34" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_30211a74-a979-43c8-b758-ef1ba600dc40" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_48dfaa3d-0fe0-4ca5-8841-3bbe2d627292" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_30211a74-a979-43c8-b758-ef1ba600dc40" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_30211a74-a979-43c8-b758-ef1ba600dc40_default" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_30211a74-a979-43c8-b758-ef1ba600dc40" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_30211a74-a979-43c8-b758-ef1ba600dc40_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_4a13d401-e06a-4f4c-a6a5-2cd41d0af477" xlink:href="https://xbrl.fasb.org/us-gaap/2022/elts/us-gaap-2022.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_30211a74-a979-43c8-b758-ef1ba600dc40" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_4a13d401-e06a-4f4c-a6a5-2cd41d0af477" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bah_EverWatchMember_c55d7fe6-1ecb-47b2-9fe9-4b0e5d22294b" xlink:href="bah-20220930.xsd#bah_EverWatchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_4a13d401-e06a-4f4c-a6a5-2cd41d0af477" xlink:to="loc_bah_EverWatchMember_c55d7fe6-1ecb-47b2-9fe9-4b0e5d22294b" xlink:type="arc" order="0"/>
  </link:definitionLink>
</link:linkbase>
