Captain of the Jolly Roger (4)
I believe the answer is:
hook
'captain of the jolly roger' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for hook that I've seen before include "stroke at Lord's?" , "One baited for fish" , "Claw" , "Curved piece of metal - boxing punch" , "Punch; fish catcher" .)