Like a wild animal (5)
I believe the answer is:
feral
'like a wild animal' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for feral that I've seen before include "Wild but formerly tame" , "Wild and menacing" , "Fierce, having reverted to wild state" , "'Savage, wild (5)'" , "beastly" .)