Spoil girl in Spanish resort (8)
I believe the answer is:
marbella
'spanish resort' is the definition.
(I've seen this before)
'spoil girl' is the wordplay.
'spoil' becomes 'mar' (synonyms).
'girl' becomes 'bella' ().
'mar'+'bella'='MARBELLA'
'in' is the link.
(Other definitions for marbella that I've seen before include "Costa del Sol resort" , "Costa del Sol city" , "Spanish resort town" .)