Moan, rejecting new form of hair (5)

I believe the answer is:

plait

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'form of hair' is the definition.
(I know that plait is a type of coif)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for plait that I've seen before include "Weave hair" , "Stranded length of hair" , "Interwoven length of hair" , "Braided hair" , "Woven length of hair" .)

I've seen this clue in The Times.

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