The phrase comes from Brazilian Portuguese slang, where esmilinguido describes someone feeling weak, drained or without strength, and this clipped spelling keeps the playful way it is pronounced online. The short two second recording spread as a shareable reaction sound on soundboards and in messaging apps, where its meaning is understood even from tone alone. It stays popular because it works without context for tired Mondays, failed workouts, sleepy pets and overacted fainting scenes, and because the drawn out final word makes any ordinary slump feel theatrical.