n.
Pronunciation: ' e-th ə - ˌ l ē n
Function: noun
Date: circa 1852
1 : a colorless flammable gaseous unsaturated hydrocarbon C 2 H 4 that is found in coal gas, can be produced by pyrolysis of petroleum hydrocarbons, and occurs in plants functioning especially as a natural growth regulator that promotes the ripening of fruit
2 : a divalent hydrocarbon group C 2 H 4 derived from ethane
– eth · yl · enic \ ˌ e-th ə - ' l ē -nik, - ' le-nik \ adjective