"Gladiator" setting (5)
I believe the answer is:
arena
'gladiator setting' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for arena that I've seen before include "Performance venue" , "Area surrounded by seating, for sports, etc." , "park" , "battlefieId" , "Area in centre of sports stadium" .)