The most common and most likely answer to this crossword clue is the 8 letter word LEOPARDS
I've seen this crossword clue in The Guardian
L
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P
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More clues leading to the result LEOPARDS
Buddy explains!

The straight part
We know that "cats" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cats = leopards.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does LEOPARDS mean?
LEOPARDS noun- Panthera pardus, a large wild cat with a spotted coat native to Africa and Asia, especially the male of the species (in contrast to leopardess).
- (inexact) A similar-looking, large wild cat named after the leopard.
- A lion passant guardant.
- Any of various nymphalid butterflies of the genus Phalanta, having black markings on an orange base.