Onyx

[on-iks, oh-niks] /ˈɒn ɪks, ˈoʊ nɪks/

noun
1.
Mineralogy. a variety of chalcedony having straight parallel bands of alternating colors.
Compare .
2.
(not used technically) an unbanded chalcedony dyed for ornamental purposes.
3.
black, especially a pure or jet black.
4.
Medicine/Medical. a nail of a finger or toe.
adjective
5.
black, especially jet black.
/ˈɒnɪks/
noun
1.
a variety of chalcedony with alternating black and white parallel bands, used as a gemstone. Formula: SiO2
2.
a compact variety of calcite used as an ornamental stone; onyx marble. Formula: CaCO3
n.

mid-13c., from Old French oniche “onyx” (12c.), and directly from Latin onyx (genitive onychis), from Greek onyx “onyx-stone,” originally “claw, fingernail” (see nail (n.)). So called because the mineral’s color sometimes resembles that of a fingernail, pink with white streaks.

onyx on·yx (ŏn’ĭks)
n.

onyx
(ŏn’ĭks)
A type of chalcedony that occurs in straight and parallel bands of different colors, often black and white.

a hail; claw; hoof, (Heb. shoham), a precious stone adorning the breast-plate of the high priest and the shoulders of the ephod (Ex. 28:9-12, 20; 35:27; Job 28:16; Ezek. 28:13). It was found in the land of Havilah (Gen. 2:12). The LXX. translates the Hebrew word by smaragdos, an emerald. Some think that the sardonyx is meant. But the onyx differs from the sardonyx in this, that while the latter has two layers (black and white) the former has three (black, white, and red).