Lovely and thin (4)
I believe the answer is:
fine
I believe this clue is a double definition.
'lovely' is the first definition.
(fine can mean lovely or beautiful)
'thin' is the second definition.
(similar in meaning)
'and' acts as a link.
(Other definitions for fine that I've seen before include "Suitable" , "Penalty; exalted; brandy" , "Sheer or very good" , "Sheer or excellent" , "Usual penalty for parking offence" .)