Game played on a lawn (7)
I believe the answer is:
croquet
'game played on a lawn' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for croquet that I've seen before include "Ball-game" , "Game which involves driving balls through hoops" , "Game with wooden balls, mallets and hoops" , "... or possibly at this ball game" , "Lawn sport" .)