Most daring undergarments (7)

I believe the answer is:

bravest

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

I cannot understand how the rest of the clue works.

(Other definitions for bravest that I've seen before include "Most heroic" , "Most valiant" , "Most courageous" , "Most handsome" , "Most daring" .)

I've seen this clue in The Daily Express.

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