Girl - South American girl (7)
I believe the answer is:
susanna
'girl' is the definition.
'south american girl' is the wordplay.
'south american' becomes 'sus' (I've seen this in other clues).
'girl' becomes 'anna' (**).
'sus'+'anna'='SUSANNA'
(Other definitions for susanna that I've seen before include "Girl" , "Girl's name; Figaro's bride" , "Her story is apocryphal" .)