Quite beautiful (6)
I believe the answer is:
pretty
I believe this clue is a double definition.
'quite' is the first definition.
(synonyms)
'beautiful' is the second definition.
(similar in meaning)
(Other definitions for pretty that I've seen before include "pulchritudinous" , "Fairly; appealing" , "Film with Julia Roberts (belle)" , "Nice to look at" , "Somewhat - attractive" .)