Overrating gin, I stirred up a tonic (14)

I believe the answer is:

reinvigorating

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'up a tonic' is the definition.
I can't judge whether this definition defines the answer.

'overrating gin i stirred' is the wordplay.
'stirred' indicates an anagram.
'overrating'+'gin'+'i'='overratinggini'
'overratinggini' is an anagram of 'REINVIGORATING'.

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I've seen this clue in The Telegraph.

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