Ocean wrong for such a vessel (5)
I believe the answer is:
canoe
'such a vessel' is the definition.
(canoe is a kind of vessel)
'ocean wrong' is the wordplay.
'wrong' indicates anagramming the letters.
'ocean' with letters rearranged gives 'CANOE'.
'for' acts as a link.
(Other definitions for canoe that I've seen before include "Small boat with paddles" , "Boat one paddles" , "Simple boat" , "Small boat for paddling" , "Primitive boat" .)