Soldier not sharing things with others (7)

I believe the answer is:

private

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'soldier' is the definition.
(private is a type of soldier)

I cannot understand how the remainder of the clue works.

(Other definitions for private that I've seen before include "'Saving - - Ryan' (film)" , "Confidential sort of soldier" , "Unofficial; military rank" , "To most, unknown" , "Secret - serviceman" .)

I've seen this clue in The Daily Express.

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