Frivolous repartee unwelcome in time (8)

I believe the answer is:

badinage

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'frivolous repartee' is the definition.
(I've seen this before)

'unwelcome in time' is the wordplay.
'unwelcome' becomes 'bad' (I can't justify this - if you can you should believe this answer much more).
'time' becomes 'age' (an age is a period of time).
'bad'+'in'+'age'='BADINAGE'

Can you help me to learn more?

(Other definitions for badinage that I've seen before include "Playful banter" , "Frivolous banter" , "Beg Diana for light banter" , "Wordplay" , "Humorous, witty conversation" .)

I've seen this clue in The Independent.

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