Definition of: topaz

(tō′paz) noun
1. A native fluosilicate of aluminum, often found in yellow prismatic crystals valued as gemstones.
2. The yellow sapphire, a highly prized corundum of Ceylon: also called Oriental topaz.
3. Citrine (def. 2).
4. Either of two large tropical American hummingbirds (Topaza pyra and T. pella) with brilliant green–and–gold plumage.
5. A brownish–gold color, the color of the mineral. [<OF topaze, topace <L topazus <Gk. topazos]