It exudes from the old soldier (5)

I believe the answer is:

sweat

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'soldier' is the definition.
(I've seen this before)

I don't understand how the remainder of the clue works.

(Other definitions for sweat that I've seen before include "Trouble in Australia" , "Salty fluid secreted by glands" , "Soldier" , "Toil" , "Salty fluid secreted by the body" .)

I've seen this clue in the Evening Standard.

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