Possibly ruder to an artist! (5)
I believe the answer is:
durer
'an artist' is the definition.
(I've seen this before)
'possibly ruder' is the wordplay.
'possibly' indicates an anagram.
'ruder' is an anagram of 'DURER'.
'to' is the link.
(Other definitions for durer that I've seen before include "Picture-maker" , "From Renaissance artist" , "Albrecht -, C15-16 German artist" , "Albrecht -, Ger. artist" , "Albrecht -, fifteenth to sixteenth century German artist" .)