Racetrack (4)
I believe the answer is:
oval
'racetrack' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for oval that I've seen before include "Egg-shaped - cricket ground" , "Courageous" , "34 [CRICKETER] 's domain" , "sports ground" , "Ellipsoidal" .)