Tō′paz, n.

n. [Fr. topaze, Pr. topazi, Sp. topacio, Pg. & It. topazio, Lat. topazion, topazon, Gr. τόπας, τοπάσιος, τοπάσιον, probably from Skr. tapas, fire, the sun, from tap, to heat. According to some, the name is from Topazos, a small isle in the Arabic Gulf, where the Romans obtained a stone which they called by this name, but which is the chrysolite of the moderns.] (Min.) A mineral occurring in rhombic prisms, generally yellowish and pellucid, also colorless, and of greenish, bluish, or brownish shades; sometimes massive and opaque, and consisting of silica, alumina, and fluoric acid. It is highly valued as a gem. Dana.