Grasping we’ve upset the well-known singer (4)

I believe the answer is:

diva

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'singer' is the definition.
(diva can mean a female opera singer)

I don't understand the rest of the clue.

(Other definitions for diva that I've seen before include "One who sings" , "Avid like opera singer" , "Top opera singer" , "Prima dona" , "Great singer" .)

I've seen this clue in the Evening Standard.

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