Chaos; dining hall (4)
I believe the answer is:
mess
I believe this is a double definition.
'chaos' is the first definition.
(I've seen this in another clue)
'dining hall' is the second definition.
(I've seen this in another clue)
(Other definitions for mess that I've seen before include "Place to eat" , "terrible state" , "State of confusion or untidiness" , "Mix-up" , "Canteen - chaos" .)