Crossword Genius

At least he's private (7)

Ross

I believe the answer is:

soldier

I'm a little stuck... Click here to teach me more about this clue!

'private' is the definition.
(I know that private is a type of private)

'at least he's' is the wordplay.
I cannot quite understand how this works, but
'he' could be 'sol' and 'sol' is found within the answer.
The remaining letters 'dier' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

(Other definitions for soldier that I've seen before include "piece of bread" , "Enlisted man or woman" , "One of man's 22 20 [SEVEN AGES]" , "Eg, private" , "Military person" .)

I've seen this clue in The Globe and Mail.
Want a hint initially instead of a full solution? Install my app