(n.) A rare metallic element, of the same group as platinum, which it much resembles, being silver-white, but harder, and brittle, and indifferent to most corrosive agents. With the exception of osmium, it is the heaviest substance known, its specific gravity being 22.4. Symbol Ir. Atomic weight 192.5.
|a heavy brittle metallic element of the platinum group, used in alloys, occurs in natural alloys with platinum or osmium|