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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019cdfab-1302-7614-aa38-9fbd1e1d8f89,g:c534b1b9-ba9e-4388-8b91-187dc834ad2f-->
<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://archer.com/role/CoverCover" xlink:type="simple" xlink:href="achr-20260309.xsd#CoverCover"/>
  <link:definitionLink xlink:role="http://archer.com/role/CoverCover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_019cdfab-1302-7c62-ad56-40297432a7a3" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_DocumentInformationTable_019cdfab-1302-7c62-ad56-40297432a7a3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019cdfab-1302-79dd-af08-c5ba9d23f4b9" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_019cdfab-1302-7c62-ad56-40297432a7a3" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019cdfab-1302-79dd-af08-c5ba9d23f4b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019cdfab-1302-79dd-af08-c5ba9d23f4b9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019cdfab-1302-79dd-af08-c5ba9d23f4b9" xlink:to="loc_us-gaap_ClassOfStockDomain_019cdfab-1302-79dd-af08-c5ba9d23f4b9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019cdfab-1302-7661-aa0f-fa03f358a8c6" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019cdfab-1302-79dd-af08-c5ba9d23f4b9" xlink:to="loc_us-gaap_ClassOfStockDomain_019cdfab-1302-7661-aa0f-fa03f358a8c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019cdfab-1302-718e-8f1b-516428d7a59c" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019cdfab-1302-7661-aa0f-fa03f358a8c6" xlink:to="loc_us-gaap_CommonClassAMember_019cdfab-1302-718e-8f1b-516428d7a59c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_019cdfab-1302-79c1-8f1e-c289eaee06cd" xlink:href="https://xbrl.fasb.org/us-gaap/2024/elts/us-gaap-2024.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019cdfab-1302-7661-aa0f-fa03f358a8c6" xlink:to="loc_us-gaap_WarrantMember_019cdfab-1302-79c1-8f1e-c289eaee06cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019cdfab-1302-79d6-a99d-0d1bd627b2cc" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_DocumentType_019cdfab-1302-79d6-a99d-0d1bd627b2cc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019cdfab-1302-7f98-bc15-f81f462e3a16" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_DocumentPeriodEndDate_019cdfab-1302-7f98-bc15-f81f462e3a16" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019cdfab-1302-7643-a0d3-202d993d072a" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityRegistrantName_019cdfab-1302-7643-a0d3-202d993d072a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019cdfab-1302-720b-bbcd-ca4854faf27a" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019cdfab-1302-720b-bbcd-ca4854faf27a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019cdfab-1302-7bd4-8bb9-86d18485658d" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityFileNumber_019cdfab-1302-7bd4-8bb9-86d18485658d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_019cdfab-1302-737e-831e-4ffede9c4662" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityTaxIdentificationNumber_019cdfab-1302-737e-831e-4ffede9c4662" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019cdfab-1302-729d-90c8-40a00dec3b63" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityAddressAddressLine1_019cdfab-1302-729d-90c8-40a00dec3b63" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019cdfab-1302-79db-9f8a-0dcfe5739e24" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityAddressCityOrTown_019cdfab-1302-79db-9f8a-0dcfe5739e24" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_019cdfab-1302-7632-9bb2-f3d2b9b28316" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityAddressStateOrProvince_019cdfab-1302-7632-9bb2-f3d2b9b28316" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019cdfab-1302-7377-9c4a-dc608bcbc216" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityAddressPostalZipCode_019cdfab-1302-7377-9c4a-dc608bcbc216" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019cdfab-1302-7d71-a8e5-e8c3d6a00155" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_CityAreaCode_019cdfab-1302-7d71-a8e5-e8c3d6a00155" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019cdfab-1302-730b-80c2-6ca7d6a8f859" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_LocalPhoneNumber_019cdfab-1302-730b-80c2-6ca7d6a8f859" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_019cdfab-1302-7c78-8d69-a58a68cdf082" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_WrittenCommunications"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_WrittenCommunications_019cdfab-1302-7c78-8d69-a58a68cdf082" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_019cdfab-1302-79f6-a8a4-3aee3abade85" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SolicitingMaterial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_SolicitingMaterial_019cdfab-1302-79f6-a8a4-3aee3abade85" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_019cdfab-1302-7ab3-855d-3d33bb24d78c" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_PreCommencementTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_PreCommencementTenderOffer_019cdfab-1302-7ab3-855d-3d33bb24d78c" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_019cdfab-1302-7ed6-997b-885dc4cf7494" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_019cdfab-1302-7ed6-997b-885dc4cf7494" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019cdfab-1302-74c0-8497-bd1bc56e6928" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityEmergingGrowthCompany_019cdfab-1302-74c0-8497-bd1bc56e6928" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019cdfab-1302-7313-9687-382163d730d7" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_Security12bTitle_019cdfab-1302-7313-9687-382163d730d7" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019cdfab-1302-7441-8bf3-751e15185766" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_TradingSymbol_019cdfab-1302-7441-8bf3-751e15185766" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019cdfab-1302-774f-89a5-68273a2741ed" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_SecurityExchangeName_019cdfab-1302-774f-89a5-68273a2741ed" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019cdfab-1302-7729-8d48-ea6e883cca31" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_EntityCentralIndexKey_019cdfab-1302-7729-8d48-ea6e883cca31" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019cdfab-1302-7fdc-9c75-b09789feb40d" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019cdfab-1302-7721-a402-53ae9e459b27" xlink:to="loc_dei_AmendmentFlag_019cdfab-1302-7fdc-9c75-b09789feb40d" xlink:type="arc" order="21"/>
  </link:definitionLink>
</link:linkbase>
