n. Chem. a gaseous hydrocarbon of the alkene series, occurring in natural gas and used in the manufacture of polythene. Also called ETHENE. °Chem. formula: C
[ 2 ]
H
[ 4 ]
. ethylene glycol Chem. a colourless viscous hygroscopic liquid used as an antifreeze and in the manufacture of polyesters. °Chem. formula: C
[ 2 ]
H
[ 6 ]
O
[ 2 ]
.: also called ETHANEDIOL. ethylenic adj.