Animal artist, tip-top (3)
I believe the answer is:
rat
'animal' is the definition.
(I know that rat is a type of scoundrel)
'artist tip-top' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'tip-top' becomes 't' (top of the word 'tip-').
'ra'+'t'='RAT'
(Other definitions for rat that I've seen before include "that gets out of stricken vessel" , "Abandon" , "Destructive rodent" , "Inform" , "Plague-carrying rodent" .)