[ on-iks, oh-niks ]
/ ˈɒn ɪks, ˈoʊ nɪks /


Mineralogy. a variety of chalcedony having straight parallel bands of alternating colors.Compare Mexican onyx.
(not used technically) an unbanded chalcedony dyed for ornamental purposes.
black, especially a pure or jet black.
Medicine/Medical. a nail of a finger or toe.


black, especially jet black.

Origin of onyx

1250–1300; Middle English onix < Latin onyx < Greek ónyx nail, claw, veined gem
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for onyx

British Dictionary definitions for onyx

/ (ˈɒnɪks) /


a variety of chalcedony with alternating black and white parallel bands, used as a gemstone. Formula: SiO 2
a compact variety of calcite used as an ornamental stone; onyx marble. Formula: CaCO 3

Word Origin for onyx

C13: from Latin from Greek: fingernail (so called from its veined appearance)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for onyx

[ ŏnĭks ]


A collection of pus in the anterior chamber of the eye.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for onyx

[ ŏnĭks ]

A type of chalcedony that occurs in straight and parallel bands of different colors, often black and white.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.