Light area (4)
I believe the answer is:
land
I believe this is a double definition.
'light' is the first definition.
(I've seen this before)
'area' is the second definition.
(land area is a kind of area)
(Other definitions for land that I've seen before include "win" , "Country, state" , "Disembark" , "Women farm workers in World War II" , "Property" .)