The phrase mexendo popo comes from Brazilian Portuguese slang, where popo is a childish word for butt and mexendo means moving or shaking it. The clip circulated as a short shareable meme audio rather than as part of a known song or show, passed around in WhatsApp groups and short video edits. Its appeal is how directly the chant describes the action on screen, making it reusable for dances, animals, game characters and anyone caught wiggling. That simplicity keeps it in rotation for quick reaction edits online.