One girl captivated by European etiquette (9)
I believe the answer is:
politesse
'etiquette' is the definition.
(I've seen this before)
'one girl captivated by european' is the wordplay.
'one' becomes 'I' (Roman numeral).
'girl' becomes 'tess' ().
'captivated by' indicates putting letters inside.
'european' becomes 'pole' (someone from Poland).
'i'+'tess'='itess'
'itess' placed into 'pole' is 'POLITESSE'.
(Other definitions for politesse that I've seen before include "Chivalry" , "Etiquette" , "formal courtesy" .)