Overlook trick performed (7)
I believe the answer is:
condone
'overlook' is the definition.
(thesaurus)
'trick performed' is the wordplay.
'trick' becomes 'con' (I've seen this before).
'performed' becomes 'done' (I've seen this before).
'con'+'done'='CONDONE'
(Other definitions for condone that I've seen before include "Overlook - forgive" , "Turn a blind eye" , "Nod once (anag) -- make allowances for" , "Accept (wrong behaviour)" , "Reluctantly sanction" .)