Dictionary entry

νῖκος

G. Abbott-Smith's A Manual Greek Lexicon of the New Testament

νῖκος, -ους, τό, late form of νίκη,

[in LXX: La 3:18 (נֶצַח), I Es 3:9, II Mac 10:38, IV Mac 17:12; εἰς ν. (instead of εἰς τέλος, Jb 14:20), II Ki 2:26, Jb 36:7, Am 1:118:7, Je 3:5, La 5:20 (לָנֶצֵח, as נ׳ in Syr., = victory)*;]

victory: Mt 12:20 (Is 42:3, LXX ἀλήθεια), I Co 15:54 (Is 25:8, Aq., Th.), I Co 15:55 (Ho 13:14, LXX δίκη), I Co 15:57.†