Pass over a region in chaos (6)
I believe the answer is:
ignore
'pass over' is the definition.
(I've seen this before)
'a region in chaos' is the wordplay.
'in chaos' indicates an anagram.
'region' is an anagram of 'IGNORE'.
(Other definitions for ignore that I've seen before include "Brush off" , "Turn a blind eye to" , "Slight" , "Spurn" , "Walk away from" .)