LATIN DICTIONARYLexicon Latīnum
noun · masculinethird declension

onyx

onyx m (genitive onychis or onychos)
Classical[ˈɔ.nyks]Ecclesiastical[ˈɔː.niks]

Meaning

  1. masculineonyx (yellow marble)
  2. masculinea yellowish precious stone
  3. masculinethe female of a mussel of the scallop species

Declension

declension
formsingularplural
nominativeonyxonychē̆s
genitiveonychis
onychos		onychum
dativeonychīonychibus
accusativeonychem
onycha		onychēs
onychas
ablativeonycheonychibus
vocativeonyxonychē̆s

ŏnyx, ўchis, m. and f., = ὄνυξ (a fingernail; hence, from its color).
I. Fem., a kind of yellowish marble, onyx, of which vessels of many kinds were made; it was also used for mlaying floors, Plin. 36, 7, 12, § 59: totāque effusus in aulā Calcabatur onyx, Luc. 10, 116; calcatusque tuo sub pede lucet onyx, Mart. 12, 50, 4.—
B. Masc., a vessel of onyx, an onyx-box: nardi parvus onyx, Hor. C. 4, 12, 17; murrheus, an ointment-box, Prop. 3, 8 (4, 9), 22; cf.: Syrio munere plenus onyx, id. 2, 10 (3, 5), 14.— In this signif. also as fem.: unguentum fuerat, quod onyx modo parva gerebat, Mart. 7, 94, 1.—
II. A yellowish precious stone, an onyx, Plin. 37, 6, 24, § 90—
III. The female of a mussel of the scallop species, Plin. 32, 9, 32, § 103.

Origins

From Ancient Greek ὄνῠξ (ónŭx, “nail”).

Quick answers

What does onyx mean in Latin?
onyx, a noun, means “onyx (yellow marble); a yellowish precious stone; the female of a mussel of the scallop species”.
What is the genitive of onyx?
The genitive singular is onychis. onyx is masculine, third declension.
How do you pronounce onyx?
In classical Latin, [ˈɔ.nyks]; in ecclesiastical (church) Latin, [ˈɔː.niks].