Under threes dancing round newspaper boss (9)

I believe the answer is:

etherised

'under' is the definition.
(under anaesthetic - ether is an old anaesthetic)

'threes dancing round newspaper boss' is the wordplay.
'dancing' indicates an anagram.
'round' indicates putting letters inside.
'newspaper' becomes 'i' (UK newspaper).
'boss' becomes 'ed' (short for editor - newspaper boss).
'threes' is an anagram of 'ethers'.
'ethers' placed around 'i' is 'etheris'.
'etheris'+'ed'='ETHERISED'

I've seen this clue in The Guardian.

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