Grazing animal left in splendid meadows (9)
I believe the answer is:
grassland
'meadows' is the definition.
(meadows are grassy regions)
'grazing animal left in splendid' is the wordplay.
'grazing animal' becomes 'ass' (donkey).
'left' becomes 'l' (common abbreviation).
'in' is an insertion indicator.
'splendid' becomes 'grand' (I've seen this in another clue).
'ass'+'l'='assl'
'assl' inserted inside 'grand' is 'GRASSLAND'.
(Other definitions for grassland that I've seen before include "green countryside" , "Large area suitable for grazing" , "Plain" , "pasture" , "(growth area)" .)