topaz

[ toh-paz ]
/ ˈtoʊ pæz /

noun

a mineral, a fluosilicate of aluminum, usually occurring in prismatic orthorhombic crystals of various colors, and used as a gem.
either of two South American hummingbirds, Topaza pella or T. pyra, having chiefly red and crimson plumage and a yellowish-green throat with a topaz sheen.

Origin of topaz

1225–75; < Latin topazus < Greek tópazos; replacing Middle English topace < Old French < Latin, as above

Related forms

to·paz·ine [toh-puh-zeen, -zin] /ˈtoʊ pəˌzin, -zɪn/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for topaz

British Dictionary definitions for topaz

topaz

/ (ˈtəʊpæz) /

noun

a white or colourless mineral often tinted by impurities, found in cavities in igneous rocks and in quartz veins. It is used as a gemstone. Composition: hydrated aluminium silicate. Formula: Al 2 SiO 4 (F,OH) 2 . Crystal structure: orthorhombic
oriental topaz a yellowish-brown variety of sapphire
false topaz another name for citrine
  1. a yellowish-brown colour, as in some varieties of topaz
  2. (as adjective)topaz eyes
either of two South American hummingbirds, Topaza pyra and T. pella

Word Origin for topaz

C13: from Old French topaze, from Latin topazus, from Greek topazos
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

Science definitions for topaz

topaz

[ tōpăz′ ]

A colorless, blue, yellow, brown, or pink orthorhombic mineral valued as a gem. Topaz occurs as transparent or translucent prisms in silica-rich igneous rocks, such as pegmatite, and in tin-bearing rock veins. Chemical formula: Al2SiO4(F,OH)2.
Any of various yellow gemstones, especially a yellow variety of sapphire or corundum.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.