Grassy field
I believe the answer is:
lea
'grassy field' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for lea that I've seen before include "Field" , "Grazing land" , "'The lowing herd wind slowly o'er the . . .'" , "Open arable land (poet.)" , "grazing area" .)