Bring back space for uncultivated land (4)
I believe the answer is:
moor
'uncultivated land' is the definition.
(a moor is wild land)
'bring back space' is the wordplay.
'bring back' is a reversal indicator.
'space' becomes 'room' (enough space or room to do something).
'room' back-to-front is 'MOOR'.
'for' is the link.
(Other definitions for moor that I've seen before include "Ground that's high" , "Room for a Muslim from N Africa" , "Heath; berth" , "North African - secure a boat - tract of land" , "Wild land; tie up" .)