District accommodating new stadium (5)
I believe the answer is:
arena
'stadium' is the definition.
('arena' can be a synonym of 'stadium')
'district accommodating new' is the wordplay.
'district' becomes 'area' (I've seen this before).
'accommodating' is an insertion indicator.
'new' becomes 'n'.
'area' going around 'n' is 'ARENA'.
(Other definitions for arena that I've seen before include "centre of conflict" , "Venue for contests" , "Central area in sports stadium" , "Sporting enclosure" , "Scene of open conflict" .)