Chalk remover (6)
I believe the answer is:
eraser
'chalk remover' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for eraser that I've seen before include "Item used for rubbing out" , "A student's rubber, or the one who uses it" , "Required, should you make a mistake" , "Piece of rubber for deleting pencil marks" , "India rubber" .)