Crocus

n.
  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.
  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.
    3. Crocus of Venus (Old Chem.),
    oxide of copper.