Picture harbour with fish (7)
I believe the answer is:
portray
'picture' is the definition.
(I've seen this before)
'harbour with fish' is the wordplay.
'harbour' becomes 'port' (I've seen this before).
'with' means one lot of letters go next to another.
'fish' becomes 'ray' (ray is a kind of fish).
'port'+'ray'='PORTRAY'
(Other definitions for portray that I've seen before include "Use words to describe" , "Delineate" , "Play" , "sketch" , "Act" .)