What is "carbonyl chloride"

Phosgene \Phos"gene\, a. [Gr. fw^s light + the root of gi`gnesqai to be born: cf. F. phosg[`e]ne.] (Old Chem.) Producing, or produced by, the action of light; -- used specifically to designate a gas also called carbonyl chloride. See Carbonyl.

n. (context inorganic compound English) A toxic gas, COCl₂, used in the manufacture of plastics, pesticides etc, and once used as a chemical weapon.