Novice varies treatment for circulation problem (8,4)

I believe the answer is:

varicose vein

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'circulation problem' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.

'novice varies treatment' is the wordplay.
'treatment' indicates an anagram (the letters must be processed or treated).
'novice'+'varies'='novicevaries'
'novicevaries' anagrammed gives 'VARICOSE VEIN'.

'for' is the link.

Can you help me to learn more?

I've seen this clue in The Daily Express.

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