Abbott-Smith Manual Greek Lexicon
ἑταῖρος (G2083)
3 ἑταῖρος , -ου, ὁ [in LXX chiefly for רֵעַ and cognate forms, also Si 11:6 37:2 ff. , al. ;] a companion, comrade : Mt 11:16 (WH, ἑτέροις ); voc., as term of address, my friend : Mt 20:13 22:12 26:50 .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain