Condiment is no longer somewhat timeless (6)
I believe the answer is:
wasabi
'condiment' is the definition.
(I know that wasabi is a type of condiment)
'is no longer somewhat timeless' is the wordplay.
'is no longer' becomes 'was' (eg if someone 'was' sad, they're no longer sad).
'somewhat timeless' becomes 'abi' (I can't justify this - if you can you should give a lot more credence to this answer).
'was'+'abi'='WASABI'
Can you help me to learn more?
(Other definitions for wasabi that I've seen before include "'Japanese plant, often eaten with raw fish (6)'" , "Pungent green root, used in Japanese cooking" , "Pungent green root used in Japanese cookery" , "Hollyhock" , "Herb" .)