A leading style of headgear or woman's top (6)

I believe the answer is:

halter

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'woman's top' is the definition.
(I've seen this in another clue)

I can't explain the remainder of the clue.

(Other definitions for halter that I've seen before include "Tether" , "device for leading Arabs" , "one that pulls up?" , "Rope for leading a horse" , "When there's harness" .)

I've seen this clue in the Evening Standard.

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