Cat turned up with mum (4)
I believe the answer is:
puma
'cat' is the definition.
(puma is a kind of cat)
'turned up with mum' is the wordplay.
'turned' says the letters should be written backwards.
'with' is a charade indicator (letters next to each other).
'mum' becomes 'ma' (ma can mean mother).
'up' reversed gives 'pu'.
'pu'+'ma'='PUMA'
(Other definitions for puma that I've seen before include "Mountain lion" , "Cougar" , "South American cat" , "Large mountain cat" , "American wildcat" .)