Meadow, pasture (3)
I believe the answer is:
This clue is a double definition.
'meadow' is the first definition.
(a lea is a grassy area)
'pasture' is the second definition.
(both can mean a field)
(Other definitions for lea that I've seen before include "''The lowing herd winds slowly o'er the ... '' (Gray)" , "Open arable land (poet.)" , "Field" , "Pasture, London river" , "authority for teachers" .)