Sir Peter the painter (4)

I believe the answer is:

lely

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'painter' is the definition.
(I have seen 'Dutch painter' mean 'lely' so perhaps 'painter' could also mean 'lely')

I can't explain the remainder of the clue.

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(Other definitions for lely that I've seen before include "Dutch artist painting in England" , "Peter -, C 17 portraitist" , "Dutch painter" , "Sir Peter -, C 17 painter" .)

I've seen this clue in the Evening Standard.

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