How one resents being cut! (6)

I believe the answer is:

keenly

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'how' is the definition.
Both the answer and definition are adverbs. Maybe they are linked in a way I don't understand?

I can't explain the remainder of the clue.

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(Other definitions for keenly that I've seen before include "Eagerly, sharply" , "Eagerly, enthusiastically" , "In an eager manner" , "With eagerness" , "With enthusiasm" .)

I've seen this clue in the Evening Standard.

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