Barrel with neatly gutted fish (5)
I believe the answer is:
tunny
'fish' is the definition.
(I know that tunny is a type of food fish)
'barrel with neatly gutted' is the wordplay.
'barrel' becomes 'tun' (tun is a kind of barrel).
'with' says to put letters next to each other.
'gutted' says to hollow out the word (remove centre letters) (to gut something is to remove its insides).
'neatly' with its centre taken out is 'ny'.
'tun'+'ny'='TUNNY'
(Other definitions for tunny that I've seen before include "Marine fish, the bluefin" , "A tuna" , "Warm water food fish" , "Common food fish" , "Large marine fish" .)