Fish that's been smoked (5)
I believe the answer is:
roach
'fish' is the definition.
(roach is a type of fish)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for roach that I've seen before include "Silvery freshwater fish" , "Fish - part of a cannabis cigarette" , "Animal found in the water" , "Something fishy here" , "Trim" .)