Fish found in buffet car, perhaps (4)
I believe the answer is:
carp
'fish found in buffet' is the definition.
'carp' can be an answer for 'fish' (I've seen this before). I'm not certain of the 'found in buffet' bit.
'car perhaps' is the wordplay.
'perhaps' becomes 'p' (this could be a standard abbreviation of which I'm unaware).
'car'+'p'='CARP'
Can you help me to learn more?
(Other definitions for carp that I've seen before include "Fish - complaint" , "Moan; fish" , "Complain continually" , "Fish - make captious criticism" , "praise? The opposite" .)