Quick Definition
ζῆλος, ου, ὁ n.m. & n.n. eagerness, zeal, rivalry
Strong's Definition
from 2204; properly, heat, i.e. (figuratively) "zeal" (in a favorable sense, ardor; in an unfavorable one, jealousy, as of a husband (figuratively, of God), or an enemy, malice)
KJV Usage: emulation, envy(-ing), fervent mind, indignation, jealousy, zeal
UBS Dictionary of the Greek New Testament
noun, m./n. | -ου, -ους | ζηλόω
25.46 · Attitudes and Emotions · Love, Affection, Compassion
devotion to, earnest concern having a deep concern for or devotion to someone or something
JHN 2:17 · ROM 10:2 · 2CO 7:7 · 2CO 7:11 · 2CO 9:2 · 2CO 11:2 · PHP 3:6
88.162 · Moral and Ethical Qualities and Related Behavior · Envy, Jealousy
envy, jealousy, resentment a particularly strong feeling of resentment and jealousy against someone
ACT 5:17 · ACT 13:45 · ROM 13:13 · 1CO 3:3 · 2CO 12:20 · GAL 5:20 · JAS 3:14 · JAS 3:16
78.25 · Degree · Much, Little [Positive-Negative Degree]
extremely, intensely, fierce a high point on a scale of extent and implying intensity of involvement
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
ζῆλος, -ov, 6, and (in Phil. iii. 6 L T Tr WH; [2 Co. ix. 2 T Tr WH)]) τὸ ζῆλος (Ignat. ad Trall. 4; διὰ ζῆλος, Clem. Rom. 1 Cor. 4, 8 [‘‘in Clem. Rom. 88 3, 4, 5, 6 the masc. and neut. seem to be interchanged without any law” (Lghtft.). For facts see esp. Clem. Rom. ed. 2 Hilgenfeld (1876) p.7; cf. WH. App. p. 158; W.§9, N. 2; B. 23 (20)]; (fr. ζέω [Curtius § 567; Vanicek p. 757]); Sept. for τ; excitement of mind, ardor, fervor of spirit ; 1. zeal, ardor in embracing, pursuing, defending anything: 2 Co. vii. 11; ix. 2; κατὰ ζῆλος, as respects zeal (in maintaining religion), Phil. iii. 6; with gen. of the obj., zeal in behalf of, for a pers. or thing, Jn. ii. 17 fr. Ps. Ixviii. (Ixix.) 10; Ro. x. 2, (1 Mace. ii. 58; Soph. O. C. 943); ὑπέρ τινος, gen. of pers., 2 Co. vii. 7; Col. iv. 13 Rec. with subject. gen. ζήλῳ θεοῦ, with a jealousy such as God has, hence most pure and solicitous for their salvation, 2 Co. xi. 2; the jfierceness of indignation, punitive zeal, πυρός (of penal fire, which is personified [see πῦρ, fin.]), Heb. x. 27 (Is. xxvi. 11; Sap. v. 18). 2. an envious and contentious rivalry, jealousy: Ro. xiii. 13; 1 Co. iii. 3; Jas. iii. 14, 16; ἐπλήσθησαν ζήλου, Acts vy. 17; xiii. 45; plur. ζῆλοι, now the stirrings or motions of ζῆλος, now its outbursts and manifestations: 2 Co. xii. 20; Gal. v. 20; but in both pass. L T Tr [WH, yet in Gal. 1. ο. WH only in txt.] have adopted ζῆλος (ζῆλοί τε καὶ φθόνοι. Plat. lege. 3 p. 679 c.). [On the distinction between ζῆλος (which may be used in a good sense) and φθόνος (used only in a bad sense) ef. Trench, Syn. § xxvi.; Cope on Aristot. rhet. 2, 11, 1 (διὸ καὶ ἐπιεικές ἐστιν ὁ ζῆλος Kal ἐπιεικῶν, τὸ δὲ φθονεῖν φαῦλον καὶ φαύλων).}
Mounce Concise Greek Dictionary
ζῆλος zēlos 16x
generous rivalry; noble aspiration; in NT zeal, ardor in behalf of, ardent affection, Jn. 2:17; Rom. 10:2; in a bad sense, jealousy, envy, malice, Acts 13:45; Rom. 13:13; indignation, wrath, Acts 5:17
Abbott-Smith Greek Lexicon
ζῆλος, -ου, ὁ and in late Gk., also -εος, τό (II Co 9:2, Phl 3:6),
[in LXX for קִנְאָה, Nu 25:11, al.;]
zeal: II Co 7:11 9:2; κατὰ ζῆλος, Phl 3:6; c. gen. obj., Jo 2:17(LXX), Ro 10:2; seq. ὑπέρ, II Co 7:7; c. gen. subj., θεοῦ, II Co 11:2; πυρός, He 10:27 (cf. Is 26:11, Wi 5:18, and cf. Westc., in l.).
jealousy: Ro 13:13, I Co 3:3, II Co 12:20, Ga 5:20 (WH, txt, RV), Ja 3:14, 16; πλησθῆναι ζήλου Ac 5:17 13:45; pl., ζῆλοι (v. B1., § 32, 6), Ga 5:20, WH, mg.†
Moulton & Milligan — Vocabulary of the Greek NT
ζῆλος occurs twice in the Alexandrian erotic fragment P Grenf 1. 138 (ii/B.c.) μέλλω μαίνεσθαι, ζῆλος γάρ με ἔχει Kal κατακαίομαι καταλελειμμένη, and 17 εὐδοκῶ ζήλῳ δουλεύειν ἐπι-
Liddell-Scott-Jones — Greek-English Lexicon
ζῆλος (zēlos) — zeal. ζῆλος, ου, ὁ, later εος, τό, [NT] codices optative; Doric dialect ζᾶλος [Refs]:— jealousy (= φθόνος), [Refs 8th c.BC+]: more usually in good sense, eager rivalry, emulation, [Refs 4th c.BC+]
2. with genitive person, zeal for one, ξυναίμων [Refs 5th c.BC+]; κατὰ ζῆλον Ἡρακλέους in emulation of him, [Refs 1st c.AD+]: absolutely, passion, [Refs 2nd c.BC+]
3. with genitive of things, ζῆλον.. γάμων ἔχουσα causing rivalry for my hand, [Refs 5th c.BC+]; ζ. τῶν ἀρίστων emulous desire for.., opposed to φυγὴ τῶν χειρόνων, [Refs 1st c.BC+]: plural, ambitions, [Refs 1st c.BC+]
4. fervour, zeal, [LXX+NT]; indignation, ζ. πυρός [NT]
5. personified as son of Styx, brother of Βία, Κράτος, Νίκη, [Refs 8th c.BC+]
II. pride, honour, glory, [Refs 5th c.BC+]
III. spirit, τῆς πολιτείας [Refs 2nd c.BC+]: plural, tastes, interests, τοῖς ἀπὸ διαφόρων ἐπιτηδευμάτων, βίων, ζήλων, ἡλικιῶν, [Refs 3rd c.AD+]
III.2. especially in Lit. Crit., style, τοῦ Ἀσιανοῦ λεγομένου ζήλου [Refs 1st c.BC+]