Revolutionary haircut for swimmer (9)

I believe the answer is:

redmullet

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'swimmer' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'revolutionary haircut' is the wordplay.
'revolutionary' becomes 'red' (red can informally mean communist).
'haircut' becomes 'mullet' (I can't justify this - if you can you should give a lot more credence to this answer).
'red'+'mullet'='REDMULLET'

'for' acts as a link.

Can you help me to learn more?

I've seen this clue in The Irish Times and the Irish Times (Crosaire).

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