Protected land (5,4)
I believe the answer is:
green belt
'protected land' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for green belt that I've seen before include "Designated zone around town or city, preserved from development" , "Sign of achievement at judo" , "Circle determined to preserve" , "protected area" , "Area round city with building restrictions" .)