Played a part (5)
I believe the answer is:
acted
'played a part' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for acted that I've seen before include "Cadet (anag)" , "Posed as" , "Trod the boards" , "Behaved or played a part" , "Behaved like thespian" .)