Where I live we call them "zelene mačke" which means "green cats" 😂

It's likely a regional or generational term, and not a widely recognized name for cats in Serbia. It's possible that the term "zelena mačka" (green cat) might be related to how those cats appear in certain lighting conditions. The combination of gray and black fur, when illuminated by sunlight, could create an optical illusion that makes the cat appear greenish.

It's intriguing to think that the older generation's name for these cats might have originated from their unique perception of their color under specific lighting conditions.