Sex? Nothing doing! (10)

I believe the answer is:

lovemaking

'sex?' is the definition.
(lovemaking can mean having sex)

'nothing doing' is the wordplay.
'nothing' becomes 'love' (love means zero in tennis).
'doing' becomes 'making' ('make' can be a synonym of 'do').
'love'+'making'='LOVEMAKING'

I've seen this clue in The Guardian.

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