Consented to a vice (6)
I believe the answer is:
agreed
'consented' is the definition.
(agreeing is a kind of consenting)
'a vice' is the wordplay.
'vice' becomes 'greed' (I've seen this before).
'a'+'greed'='AGREED'
'to' acts as a link.
(Other definitions for agreed that I've seen before include "Of one mind" , "Settled by common consent" , "Was fitting" , "Acquiesed, concurred" , "That's right" .)