Counselling a Democrat over bad habit (6)
I believe the answer is:
advice
'counselling' is the definition.
(I've seen this before)
'a democrat over bad habit' is the wordplay.
'democrat' becomes 'd'.
'over' is a charade indicator (letters next to each other) (in a down clue, some letters go over others).
'bad habit' becomes 'vice' (a sin or weakness).
'a'+'d'+'vice'='ADVICE'
(Other definitions for advice that I've seen before include "Guidance; delivery note" , "Suggestion (invited or otherwise)" , "Suggestion for appropriate course of action" , "Warning - guidance" , "Supposed words of wisdom" .)