Word of thanks jeered at? Not allowed (7)

I believe the answer is:

tabooed

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'at? not allowed' is the definition.
I can't judge whether this definition defines the answer.

'word of thanks jeered' is the wordplay.
'word of thanks' becomes 'ta' (informal way of saying thank you).
'jeered' becomes 'booed' (I've seen this in another clue).
'ta'+'booed'='TABOOED'

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(Other definitions for tabooed that I've seen before include "Prevented" , "Banned" .)

I've seen this clue in The Times.

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