Improperly clad, artiste may be prudish (6-5)
I believe the answer is:
strait-laced
'be prudish' is the definition.
(synonyms)
'improperly clad artiste' is the wordplay.
'improperly' indicates an anagram (I've seen this in other clues).
'clad'+'artiste'='cladartiste'
'cladartiste' anagrammed gives 'STRAIT-LACED'.
'may' acts as a link.
(Other definitions for strait-laced that I've seen before include "Strictly moral" , "Narrow-minded" , "Prudish" , "Having strict morals" .)