A noisy but honest business (6)

I believe the answer is:

affair

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'business' is the definition.
(thesaurus)

'a noisy but honest' is the wordplay.
'noisy' becomes 'f'.
'but honest' becomes 'fair' ('fair' can be similar in meaning to 'honest'. I am not sure about the 'but' bit.**).
'a'+'f'+'fair'='AFFAIR'

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(Other definitions for affair that I've seen before include "Concern -- extramarital relationship" , "Concern, matter or illicit romance" , "Social event or sexual relationship" , "Romantic relationship between two unmarried people" , "Former Belgian coin" .)

I've seen this clue in the Evening Standard.

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