Immoral behaviour (4)
(Other definitions for evil that I've seen before include "Demonic" , "Wicked - social problem" , "Great wickedness" , "A live sort of badness" , "Depraved" .)
'immoral behaviour' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for vice that I've seen before include "Getting a grip" , "Gripper - sin" , "Prefix for deputy to, say, chairman" , "In place of - depravity" , "Bad habits" .)