Painters or oculists in a state of disarray (10)

I believe the answer is:

colourists

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'painters' is the definition.
Both the definition and answer are plural nouns.
Perhaps there's an association between them I don't understand?

'or oculists in a state of disarray' is the wordplay.
'or oculists' can be anagrammed to 'COLOURISTS'.
Though, I'm unsure how the anagram is indicated.

Can you help me to learn more?

I've seen this clue in The Independent.

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