Garments for professional people? (6)

I believe the answer is:

briefs

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

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

(Other definitions for briefs that I've seen before include "Orders" , "Gives (someone) essential information" , "Underpants for lawyers?" , "Underpants for a lawyer" , "Garments" .)

I've seen this clue in the Evening Standard.

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