The honk comes from Space Station 13, a long-running multiplayer game where the clown is one of its most famous roles and the horn is the character's signature toy for causing mischief. Clips of clowns honking through stations spread through gameplay videos, streams and soundboards, where the sound became shorthand for silliness and light trolling. Like an air horn in meme edits, it still works today because it is under a second long, instantly recognisable and needs no context to land as a joke.