Definition of Ethylene 1. A flammable colorless gaseous alkene; obtained from petroleum and natural gas and used in manufacturing many other chemicals; sometimes used as an anesthetic Noun Synonyms for word "ethylene" Semanticaly linked words with "ethylene" Hyponims for word "ethylene" has derived form -ene etymology chlorotrifluoroethylene etymology cocaethylene etymology ethylenic etymology melene etymology methene etymology nonethylene etymology nonylene etymology polyethylene etymology quartene etymology tetraacetylethylenediamine etymologically related polyethylene glycol is derived from ethylene glycol is derived from ethylene oxide is derived from ethylene-vinyl acetate is derived from polyethylene is derived from polyethylene terephthalate