onyx [on-iks, oh-niks]
noun
1. Mineralogy. a variety of chalcedony having straight parallel bands of alternating colors.
Compare Mexican onyx.
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.
See more synonyms on Thesaurus.com
Origin: 1250-1300; Middle English onix < Latin onyx < Greek ónyx nail, claw, veined gem
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