Phosgene /(?)/

Phos·gene

Phosgene

a.
  1. Producing, or produced by, the action of light; -- used specifically to designate a gas also called carbonyl chloride. See phosgene, n., and Carbonyl. (Old Chem.)

phosgene

n.
  1. A reactive chemical substance (COCl2), also called carbonyl choride, used in synthesis of numerous substances. In the First World War it was also used as a poisonous gas in combat. (Chem.)