Overlook, forgive (6)
I believe the answer is:
excuse
This clue is a double definition.
'overlook' is the first definition.
(thesaurus)
'forgive' is the second definition.
(excusing is a kind of forgiving)
(Other definitions for excuse that I've seen before include "Make apologies for" , "Release (from a duty)" , "Pardon, or release from obligation" , "Defense of offensive behavior" , "Condone or forgive" .)