Desmond wouldn't wear one (4)

I believe the answer is:

tutu

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'desmond' is the definition.
(I know that desmond can be written as Tutu)

I don't understand the rest of the clue.

(Other definitions for tutu that I've seen before include "Ballerina's costume" , "very short garment" , "Archbishop Desmond" , "In which dancer may appear" , "Ballerina's stiff skirt" .)

I've seen this clue in the Evening Standard.

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