Person found down under bird (4)

I believe the answer is:

kiwi

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'down under bird' is the definition.
(I've seen this in another clue)

I don't understand the remainder of the clue.

(Other definitions for kiwi that I've seen before include "Sacred Japanese peak" , "Symbol of New Zealand" , "one with big bill" , "Flightless NZ bird" , "New Zealander (informal)" .)

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