Pronunciation: (tō'paz),[key] —n. 1. a mineral, a fluosilicate of aluminum, usually occurring in prismatic orthorhombic crystals of various colors, and used as a gem.
2. citrine (def. 2).
3. 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.