Avada Kedavra is the Killing Curse from the Harry Potter stories, one of the three Unforgivable Curses and the signature spell of Lord Voldemort and his Death Eaters. In the books and films it is cast with a burst of green light and causes instant death, which made it one of the most recognisable incantations in the franchise. As Harry Potter clips spread across YouTube, TikTok and meme edits, the sound became shorthand for removing something completely, from a rival in a game to an unwanted plot point, and it remains popular because the reference is understood instantly without context.