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† sardŏnyx, ychis, m. and f., = σαρδόνυξ, a precious stone, sardonyx; fem., Plin. 37, 6, 23, § 85; Pers. 1, 16; Juv. 7, 144.
Masc., Juv. 6, 382; Mart. 4, 28, 4; 4, 61, 6.
Gen. plur. sardonychum, Juv. 13, 139.
Hence, adj.: sardŏnĭchus, a, um, of sardonyx: lapis, Vulg. Job, 28, 16.