Obsolete twice over? (8)
I believe the answer is:
outdated
'obsolete' is the definition.
(synonyms)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for outdated that I've seen before include "No longer valid or fashionable" , "to be ignoring fashion" , "Pass" , "Obsolete, antiquated" , "Passe" .)