n. 1. A blue to blue-green mineral of aluminum and copper, mainly CuAl6(PO4)4(OH)8·4H2O, prized as a gemstone in its polished blue form. 2. A light to brilliant bluish green. [Middle English turkeis and French turquoise, both from Old French (pierre) turqueise, Turkish (stone), turquoise, feminine of turqueis, Turkish, from Turc, Turk; see TURK.] turquoise′ adj. ![]() (click for a larger image) turquoisesterling silver and turquoise belt buckle |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.