Former PM gutted fish (4)
I believe the answer is:
hake
'fish' is the definition.
(hake is a kind of fish)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for hake that I've seen before include "Type of fish" , "Swimmer" , "Food fish related to the cod" , "Common food fish" , "Food fish; rhymes with create" .)