Quick Definition
ἑταῖρος, ου, ὁ n.m. a companion, comrade
Strong's Definition
a comrade
Derivation: from (a clansman);
KJV Usage: fellow, friend
UBS Dictionary of the Greek New Testament
noun, m. | -ου
34.16 · Association · Associate
companion, friend a person who is associated with someone else, though not necessarily involving personal affection (as in the case of φίλος and φίλη, 34.11 and 34.12) This meaning is also found as a variant reading: ὁμοία ἐστὶν παιδίοις καθημένοις ἐν ταῖς ἀγοραῖς ἅ προσφωνοῦντα τοῖς ἑταίροις ‘like children sitting around in the marketplace and shouting to their companions’ MAT 11:16 (apparatus; see Nestle-Aland).
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
ἑταῖρος, -ov, ὁ, [fr. Hom. down], Sept. 1; @ comrade, mate, partner, [A. V. fellow]: Mt. xi. 16 (where T Tr WHI τοῖς ἑτέροις [q- v- 1 b., and οἵ. WH. Intr. § 4047); νοῦ. in kindly address, friend (my good friend): Mt. xx. 19. χχιϊ 19: χα 0.
Mounce Concise Greek Dictionary
ἑταῖρος hetairos 3x
a companion, associate, fellow-comrade, friend, Mt. 20:13; 22:12; 26:50*
Abbott-Smith Greek Lexicon
ἑταῖρος, -ου, ὁ
[in LXX chiefly for רֵעַ and cognate forms, also Si 11:6 37:2ff., al. ;]
a companion, comrade: Mt 11:16 (WH, ἑτέροις); voc., as term of address, my friend: Mt 20:13 22:12 26:50.†
Moulton & Milligan — Vocabulary of the Greek NT
Liddell-Scott-Jones — Greek-English Lexicon
ἑταῖρος (hetairos) — friend. ἑταῖρ-ος, Epic dialect and Doric dialect also ἕγᾰρος, [Refs 6th c.BC+], ὁ:— comrade, companion, in [Refs 8th c.BC+] especially of the followers of a chief, comrades-in-arms, [Refs 8th c.BC+]; messmate, [Refs]; fellowslave, [Refs 8th c.BC+]; later, as a term of address, φίλ᾽ ἑταῖρε [Refs 6th c.BC+]; ὦταῖρε Scol. cited in [NT+5th c.BC+] partner of my feast, [Refs]; πόσιος καὶ βρώσιος ἑταῖροι messmates, [Refs 6th c.BC+]
2. metaphorically, of things, ἐσθλὸς ἑταῖρος, of a fair wind, [Refs 8th c.BC+]
3. pupil, disciple, e.g. of Socrates, [Refs 5th c.BC+]: plural, fellow-pupils, [Refs 2nd c.AD+]
4. of political partisans [Refs 5th c.BC+]; οἱ περὶ αὐτὸν ἑ. his club-mates, [Refs 4th c.BC+]
5. members of a religious guild, [Refs]
6. rarely of lovers, [Refs 7th c.BC+]
7. ἑταῖροι, οἱ, the guards, i.e. the cavalry of the Macedonian kings, [Refs 4th c.BC+] see at {πεζέταιρος}, [Refs 2nd c.AD+]; to be distinguished from the king's immediate retinue (compare above [Refs 2nd c.AD+]; of the [Refs 1st c.AD+]
8. as adjective, associate of, τὸ ἐπιθυμητικὸν ἡδονῶν ἑ. [Refs 5th c.BC+] your closest companions, [Refs 1st c.AD+]; σαργῶν γένος πέτρῃσιν ἑ. constant to the rocks, [Refs 2nd c.AD+]: absolutely, of animals, gregarious, [Refs]
II. ἑταίρα, Ionic dialect ἑταίρη, Epic dialect ἑτάρη [ᾰ], ἡ, companion, Ἔρις..Ἄρεος..κασιγνήτη ἑτάρη τε [Refs 8th c.BC+]; Ποσειδάωνος ἑ., of a submerged city, [Refs 3rd c.BC+]
II.2. courtesan, [Refs 5th c.BC+]; opposed to πόρνη (a common prostitute), [Refs 4th c.BC+]; opposed to γαμετή, [Refs 6th c.BC+]