Pointer — remove tip from vegetable (5)
I believe the answer is:
arrow
'pointer' is the definition.
(I know that pointer can be written as arrow)
'remove tip from vegetable' is the wordplay.
'remove tip from' means to remove the first letter.
'vegetable' becomes 'marrow' (marrow is a kind of vegetable).
'marrow' with its initial letter taken off is 'ARROW'.
(Other definitions for arrow that I've seen before include "Missile with a straight thin shaft" , "Item in a quiver" , "Sharp-tipped missile" , "Pointer; bolt" , "what may have killed Harold?" .)