I believe the answer is:
'counterfoil' is the definition.
(I know that counterfoil can be written as stub)
This is all the clue.
(Other definitions for stub that I've seen before include "Objections after picking up" , "Strike against hard object - one's toe, perhaps" , "Pencil or cigarette end" , "Short bit of pencil, say" , "30 [FAG END]" .)