The atomic arrangement –C(OH)=C(OH)– produced by proton migration from the CH of a —CHOH group that is attached to a –CO– group to the oxygen of the –CO– group (usually induced by alkali), giving rise to doubly bonded carbon atoms (the -ene group), each bearing a –CHOH group (a diol); a special case of enolization.
Medical dictionary. 2011.