adjoin v. + Add to list US //əˈdʒɔɪn// UK //ɐdʒˈɔɪn// ad·join SynonymsEtymology Synonyms abutborderbuttcontactedgemarchmeettouchOriginLATadiungō→XNOadjoindre→ENadjoin From Anglo-Norman adjoindre, from Latin adiungō.