Au revoir is a standard French farewell, literally meaning until we meet again, and its short spoken form has become a handy ending sound online. With no confirmed single film, show or creator behind this specific recording, its spread comes from reuse rather than one viral moment. Editors pair it with other brief sign-off clips like bye bye mewing to close skits, gaming clips and reaction edits. Its appeal lasts because viewers instantly understand the meaning, even without speaking French, and the brevity lets it fit almost any abrupt ending.