The wolf whistle has been used as a catcall in everyday slang for decades, named after the exaggerated reaction of cartoon wolves seeing an attractive character. It became a staple of mid-20th century animation and comedy, then carried into sitcoms, adverts and variety shows as instant shorthand for attraction. Online, creators revived it as a short reaction clip for edits, memes and soundboards, where its two notes need no explanation. Its meaning survives even without the original cartoons because the melody itself has become the joke.