What's round a field? (6)
I believe the answer is:
sphere
I believe this clue is a double definition.
'what's round' is the first definition.
(thesaurus)
'a field?' is the second definition.
(I know that field can be written as sphere)
(Other definitions for sphere that I've seen before include "Orb or globe" , "Field; globe" , "All-rounder" , "Area of activity" , "Ball or field of influence" .)