Initial round in a girl's sport (8)
I believe the answer is:
original
'initial' is the definition.
(thesaurus)
'round in a girl's sport' is the wordplay.
'round' becomes 'o' (round can mean a round object).
'sport' is an anagram indicator.
'in'+'a'+'girl'='inagirl'
'inagirl' anagrammed gives 'riginal'.
'o'+'riginal'='ORIGINAL'
(Other definitions for original that I've seen before include "Phototype" , "In first form" , "Primitive, earliest" , "Archetype,master copy" , "Not copied or imitated" .)