Noun | 1. | ethylene - a flammable colorless gaseous alkene; obtained from petroleum and natural gas and used in manufacturing many other chemicals; sometimes used as an anesthetic TCE, trichloroethane, trichloroethylene - a heavy colorless highly toxic liquid used as a solvent to clean electronic components and for dry cleaning and as a fumigant; causes cancer and liver and lung damage gas - a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely |