Something stirring, etc, in tax reforms (8)

I believe the answer is:

excitant

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'something stirring' is the definition.
I can't judge whether this defines the answer.

'etc in tax reforms' is the wordplay.
'reforms' is an anagram indicator.
'etc'+'in'+'tax'='etcintax'
'etcintax' anagrammed gives 'EXCITANT'.

Can you help me to learn more?

(Another definition for excitant that I've seen is " Stimulant".)

I've seen this clue in The Times.

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