Empty trawler, away for fish (5)
I believe the answer is:
trout
'for fish' is the definition.
(trout is a kind of fish)
'empty trawler away' is the wordplay.
'empty' suggests removing the centre.
'away' becomes 'out' (similar in meaning).
'trawler' with its centre removed is 'tr'.
'tr'+'out'='TROUT'
(Other definitions for trout that I've seen before include "old bag" , "It rises to fly" , "Fish - old harridan" , "one may be hooked" , "Fish (associated with Schubert?)" .)