Fierce word of reproof? (3)

I believe the answer is:

fie

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If this is the answer I cannot explain how the clue works.

(Other definitions for fie that I've seen before include "Cry of dismay" , "Yuck!" , "Exclamation of mock dismay" , "Expression of disgust or outrage" , "Shame!" .)

I've seen this clue in the Evening Standard.

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