More sophisticated Scottish girl in credit (8)
I believe the answer is:
classier
'more sophisticated' is the definition.
(I've seen this before)
'scottish girl in credit' is the wordplay.
'scottish girl' becomes 'lassie' (I've seen this before).
'in' is an insertion indicator.
'credit' becomes 'cr' (abbreviation).
'lassie' put inside 'cr' is 'CLASSIER'.
(Other definitions for classier that I've seen before include "More sophisticated or stylish" , "Tony increasingly" , "superior?" , "Smarter" .)