Hairstyle that might be red or grey? (6)

I believe the answer is:

mullet

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'hairstyle' is the definition.
(I know that Mullet is a hairstyle)

I cannot understand how the rest of the clue works.

(Other definitions for mullet that I've seen before include "Fish (red or grey)" , "Fish's name for a hairstyle" , "Fish - bad haircut" , "Barnet?" , "swimmer" .)

I've seen this clue in The Telegraph and The Sun.

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