Pen witticism, funny phrase I love? (8)

I believe the answer is:

aphorise

'pen witticism' is the definition.
(write an aphorism)

'funny phrase i love?' is the wordplay.
'funny' indicates anagramming the letters.
'love?' becomes 'o' (love means zero in tennis).
'phrase'+'i'+'o'='phraseio'
'phraseio' with letters rearranged gives 'APHORISE'.

I've seen this clue in The Guardian.

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