Something outdated (3,3)
I believe the answer is:
old hat
'something outdated' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for old hat that I've seen before include "A tediously familiar thing" , "Tediously familiar like ancient headgear" , "Out of date like ancient headgear" , "Boringly familiar" , "not the gear for Ascot?" .)