Draw back well-uphostered part (4)
I believe the answer is:
pull
'draw' is the definition.
(synonyms)
'back well-uphostered part' is the wordplay.
'back' shows that the letters should be reversed in order.
'part' indicates a hidden word.
'llup' is hidden within 'well uphostered'.
'llup' reversed gives 'PULL'.
(Other definitions for pull that I've seen before include "withdraw" , "Heave" , "Draw towards oneself" , "Tug; attraction" , "Attract as a customer" .)