Cropped male nude I sent - not in post (8)

I believe the answer is:

unmailed

'not in post' is the definition.
(not sent in the mail)

'cropped male nude i sent' is the wordplay.
'cropped male nude i' becomes 'un' (I can't explain this - if you can you should give a lot more credence to this answer).
'sent' becomes 'mailed' ('mail' can be a synonym of 'send').
'un'+'mailed'='UNMAILED'

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