Add a beat, ruining this rhyme (9)

I believe the answer is:

rhythmise

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'add a beat' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'ruining this rhyme' is the wordplay.
'ruining' indicates an anagram.
'this'+'rhyme'='thisrhyme'
'thisrhyme' anagrammed gives 'RHYTHMISE'.

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I've seen this clue in The Times.

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