propylene n 1: a flammable gas obtained by cracking petroleum; used in organic synthesis [syn: {propylene}, {propene}]
Propylene \Pro"pyl*ene\, n. [Cf. F. propyl[`e]ne.] (Chem.) A colorless gaseous hydrocarbon ({C3H6}) of the ethylene series, having a garlic odor. It occurs in coal gas, and is produced artificially in various ways. Called also {propene}. [1913 Webster]