Cat, nine, spoiling antique (7)
I believe the answer is:
ancient
'antique' is the definition.
(I've seen this before)
'cat nine spoiling' is the wordplay.
'spoiling' indicates anagramming the letters.
'cat'+'nine'='catnine'
'catnine' anagrammed gives 'ANCIENT'.
(Other definitions for ancient that I've seen before include "Of times long past" , "over the hill" , "Antediluvian" , "from Aristophanes' time" , "Bygone" .)