Crab part (4)
I believe the answer is:
claw
'crab part' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for claw that I've seen before include "Lobster's grasping structure" , "Rake" , "See 3" , "Scratch - scrape" , "Hook on the end of toe" .)