An orange Adam never had? (5)

I believe the answer is:

navel

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'an orange' is the definition.
(navel orange is a kind of orange)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for navel that I've seen before include "Something to contemplate" , "Belly button" , "Umbilicus" , "Tummy button" , "Bellybutton" .)

I've seen this clue in the Evening Standard.

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