Cover, perhaps, producing panic (4)

I believe the answer is:

flap

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'panic' is the definition.
(getting in a flap is panicking)

I cannot understand how the remainder of the clue works.

(Other definitions for flap that I've seen before include "Use wings; be agitated" , "Agitated state; tab" , "Flutter" , "Be agitated; hinged piece" , "Minor panic; tab" .)

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