Depart from advice occasionally? (3)
I believe the answer is:
die
'depart' is the definition.
(thesaurus)
'advice occasionally?' is the wordplay.
'occasionally?' means one should take alternating letters (letters taken at regular intervals or occasions).
The alternating letters of 'advice' are 'DIE'.
'from' acts as a link.
(Other definitions for die that I've seen before include "Cease living" , "It may be used in a game" , "one proverbially straight" , "One of a pair of dice" , "Cease to live" .)