Painter's eccentric traits (6)
I believe the answer is:
artist
'painter's' is the definition.
(painter is an example)
'eccentric traits' is the wordplay.
'eccentric' indicates anagramming the letters.
'traits' with letters rearranged gives 'ARTIST'.
(Other definitions for artist that I've seen before include "Expert" , "Skilled person" , "Eg, a painter" , "eg Monet" , "Painter, drawer" .)