Cro″cus (krō″kŭs), n. [L., saffron, fr. Gr. κρόκοσ; cf. Heb. karkōm, Ar. kurkum, Skr. kuṅkuma.] 1. (Bot.) A genus of iridaceous plants, with pretty blossoms rising separately from the bulb or corm. C. vernus is one of the earliest of spring-blooming flowers; C. sativus produces the saffron, and blossoms in the autumn.
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.
Crocus of Venus(Old Chem.), oxide of copper.