Organ with a hammer (3)
I believe the answer is:
ear
'organ with a hammer' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ear that I've seen before include "Fruiting head of a cereal" , "'Give every man thine ..., but few thy voice' (Hamlet)" , "Spike of, eg, corn" , "good sense of music" , "Speculator ignoring British" .)