<p><strong>Noun:</strong></p><ul><li>A mineral, a fluosilicate of aluminum, usually occurring in prismatic orthorhombic crystals of various colors, and used as a gem.</li><li>Citrine (def 2).</li><li>Either of two South American hummingbirds, <em>Topaza pella</em> or <em>T. pyra</em>, having chiefly red and crimson plumage and a yellowish-green throat with a topaz sheen.</li></ul>