Pull back piece of dustcart taillight (7)
I believe the answer is:
attract
'pull' is the definition.
(I know that pull can be written as attract)
'back piece of dustcart taillight' is the wordplay.
'back' shows that the letters should be reversed in order.
'piece of' indicates a hidden word.
'tcartta' is hidden within 'dustcart taillight'.
'tcartta' reversed gives 'ATTRACT'.
(Other definitions for attract that I've seen before include "Draw towards one, as magnet does metal" , "Draw to oneself" , "Entice" , "Allure" , "Draw, pull" .)