What is "chloroacetone"

n. (context organic compound English) The chlorinated derivative of acetone CH₃-CO-CH₂Cl used in tear gas and in organic synthesis

Chloroacetone is a chemical compound with the formula CCH. At STP it is a colourless liquid with a pungent odour. On exposure to light, it turns to a dark yellow-amber colour. It was used as a tear gas in World War I.