Tract, region (4)
I believe the answer is:
area
This clue is a double definition.
'tract' is the first definition.
(I've seen this in another clue)
'region' is the second definition.
(I know that area is a type of region)
(Other definitions for area that I've seen before include "Field of activity or surface" , "Surface measurement" , "Part of a building, city etc" , "Geographical region" , "Patch" .)