crocus

n. [ L., saffron, fr. Gr. kro`kos; cf. Heb. karkōm, Ar. kurkum, Skr. ku&ndot_;kuma. ] 1. (Bot.) A genus of iridaceous plants, with pretty blossoms rising separately from the bulb or corm. Crocus vernus is one of the earliest of spring-blooming flowers; Crocus sativus produces the saffron, and blossoms in the autumn. [ 1913 Webster ]

2. (Chem.) A deep yellow powder; the oxide of some metal calcined to a red or deep yellow color; esp., the oxide of iron (Crocus of Mars or colcothar) thus produced from salts of iron, and used as a polishing powder. [ 1913 Webster ]

Crocus of Venus (Old Chem.), oxide of copper. [ 1913 Webster ]