Region, zone (4)
I believe the answer is:
area
I believe this is a double definition.
'region' is the first definition.
(I know that region can be written as area)
'zone' is the second definition.
(I've seen this before)
(Other definitions for area that I've seen before include "Patch" , "environs" , "Space occupied by something" , "Geographical region" , "Field -- expanse" .)