advise against (8)
I believe the answer is:
dissuade
'advise against' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for dissuade that I've seen before include "Deter by advice" , "Put off" , "Try to deter" , "Persuade not to" , "Discourage from course of action" .)