alkene
noun /ˈælkiːn/
/ˈælkiːn/
(chemistry- any of a series of gases that contain hydrogen and carbon and that have a double bond (= force of attraction) between two of the atoms of carbon
烯;烯烃 词源late 19th cent.: from alkyl (German, from Alkohol ‘alcohol’ + -yl) + -ene.