Hypes vile performance in a childish way (9)

I believe the answer is:

peevishly

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'in a childish way' is the definition.
I can't judge whether this definition defines the answer.

'hypes vile performance' is the wordplay.
'performance' indicates anagramming the letters.
'hypes'+'vile'='hypesvile'
'hypesvile' is an anagram of 'PEEVISHLY'.

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I've seen this clue in The Mirror.

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