Retriever, maybe (3,3)
I believe the answer is:
gun dog
'retriever maybe' is the definition.
(I know that retriever is a type of gun dog)
This is all the clue.
(Other definitions for gun dog that I've seen before include "Canine trained to retrieve game" , "'Canine for a shooter (3,3)'" , "Game retriever" , "eg Pointer" , "one sent to return game" .)