Last chairman sacked for fraud (12)

I believe the answer is:

charlatanism

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'fraud' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Maybe there's an association between them I don't understand?

'last chairman sacked' is the wordplay.
'sacked' indicates anagramming the letters.
'last'+'chairman'='lastchairman'
'lastchairman' anagrammed gives 'CHARLATANISM'.

'for' acts as a link.

Can you help me to learn more?

(Other definitions for charlatanism that I've seen before include "Animal starch (anag) - quackery" , "Quacking" .)

I've seen this clue in The Times.

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