Actors no longer able to star? (6)
I believe the answer is:
extras
'actors' is the definition.
(extra is a kind of actor)
'no longer able to star?' is the wordplay.
I cannot quite see how this works, but
'no longer' could be 'ex' and 'ex' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for extras that I've seen before include "5 [BYE BYE]" , "Minor actors in crowd scenes" , "Actors hired for crowd scenes" , "Spear carriers" , "Runs not scored from the bat" .)