νικ-ητήριος · nik-ētērios — LSJ
belonging to a conqueror or to victory, δόξα ν. the glory of victory, Antiph. 263; ν. φίλημα a kiss as the conquerorʼs reward, X. Smp. 6.1; ἆθλα ν. Pl. Lg. 832e.
as Subst. νικητήριον (sc. ἆθλον), τό, prize of victory, Ζεῦ, σὸν τὸ ν. Ar. Eq. 1253; τὸν βοῦν ἔλαβε τὸ ν. X. Cyr. 8.3.33, cf. HG 6.2.28; ν. ἁμίλλης Inscr.Délos 464.10 (ii B.C.): mostly in pl., τῷ καλλικοτταβοῦντι νικητήρια τίθημι S. Fr. 537; ν. λαβών E. Alc. 1028; τὰ ν. οἴσεσθαι, φέρεσθαι, κομίζεσθαι, to win the prize, Pl. Euthd. 305d, Phdr. 245b, R. 612d; τὰ ν. τοῦ κιθαρῳδοῦ IG 2(2).1388.37.
νικητήρια (sc. ἱερά), τά, festival of victory, ν. ἑστιᾶν to celebrate this festival by a banquet, X. Cyr. 8.4.1, Plu. Phoc. 20; ποιεῖν D.C. 67.9.
also in pl., decisive proof, Hp. Septim. 4.