STEP Greek Lexicon: ἑταῖρος

ἑταῖρος, -ου, ὁ

[in LXX chiefly for רֵעַ and cognate forms, also Sir.11:6 37:2 ff., al. ;]

a companion, comrade: Mat.11:16 (WH, ἑτέροις); voc., as term of address, my friend: Mat.20:13 22:12 26:50.†

(AS)