Greed, a bad habit, has artist returning (7)
I believe the answer is:
avarice
'greed' is the definition.
(avarice is a kind of greed)
'a bad habit has artist returning' is the wordplay.
'bad habit' becomes 'vice' (a sin or weakness).
'has' is an insertion indicator.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'returning' shows that the letters should be reversed in order.
'ra' written backwards gives 'ar'.
'vice' placed around 'ar' is 'varice'.
'a'+'varice'='AVARICE'
(Other definitions for avarice that I've seen before include "One of seven deadly sins" , "Cupidity" , "Wanting to be rich" , "Insatiable lust" , "Sway, control" .)