Fish from a boat (4)
I believe the answer is:
dory
This clue is a double definition.
'fish' is the first definition.
(dory is a kind of fish)
'a boat' is the second definition.
(dory is a kind of boat)
'from' acts as a link.
(Other definitions for dory that I've seen before include "Marine fish; rhymes with fable" , "Sea-wolf" , "another fish wanted" , "Fish for a small boat" , "Golden-yellow fish" .)