Quite good-looking (6)
I believe the answer is:
pretty
I believe this is a double definition.
'quite' is the first definition.
(synonyms)
'good-looking' is the second definition.
(I've seen this before)
(Other definitions for pretty that I've seen before include "Facially attractive" , "Daintily good-looking, maybe as a picture" , "charming to look at" , "Fairly; appealing" , "Rather attractive" .)