In marijuana, the major taboo (8)

I believe the answer is:

anathema

'taboo' is the definition.
(thesaurus)

'in marijuana the major' is the wordplay.
'in' indicates the answer is hidden within the clue.
'ANATHEMA' is hidden within 'marijuana the major'.

(Other definitions for anathema that I've seen before include "Execration" , "Curse of the Church, or detested person" , "Bete noir" , "Something very greatly disliked" , "Curse; object of loathing" .)

I've seen this clue in The Telegraph.

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