Worry an animal (6)
I believe the answer is:
badger
I believe this clue is a double definition.
'worry' is the first definition.
(thesaurus)
'an animal' is the second definition.
(I've seen this before)
(Other definitions for badger that I've seen before include "Member of the weasel family" , "Grab Ed from the animal" , "nocturnal creature" , "Repeatedly ask (someone) to do something" , "A mammal; harry" .)