Cristiano Ronaldo developed the Siu celebration during his time at Real Madrid, explaining that si means yes in Spanish and that the shout grew from how he marked goals with teammates. He would run, jump, spin in mid-air and land shouting the word, a routine that fans in stadiums soon copied. Clips of the celebration spread widely on social media and in football games, and the isolated shout became a standalone meme sound used far beyond football for any triumphant or joking victory moment.