Partial groups groomed one’s pets (4,4)

I believe the answer is:

open sets

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'partial groups' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'groomed one's pets' is the wordplay.
'groomed' is an anagram indicator (letters groomed or tidied up).
'ones'+'pets'='onespets'
'onespets' anagrammed gives 'OPEN SETS'.

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I've seen this clue in the Sydney Morning Herald.

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