Elongated circle (4)
I believe the answer is:
oval
'elongated circle' 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 "Stretched circle?" , "Where England regained the Ashes" , "Rounded like an egg" , "6D 5A [TUBE STATION]" , "Squashed circle" .)