Fiendish finish? (3)

I believe the answer is:

end

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'finish?' is the definition.
(finishing is a kind of ending)

'fiendish' is the wordplay.
'END' is hidden within the letters.
But, I'm not sure how this is indicated.

Can you help me to learn more?

(Other definitions for end that I've seen before include "Remainder" , "Novel by Graham Greene" , "Unyielding" , "Game at bowls" , "Butt" .)

I've seen this clue in the Evening Standard.

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