Chattering teeth is a familiar novelty sound associated with the classic wind-up teeth toy, known for its fast mechanical clack. Online, the audio spread through meme edits, prank clips and reaction posts where creators use it to signal nerves, fake cold, frantic energy or chaotic talking. It remains popular because the sound is instantly readable even without context, and its toy-like rhythm fits both old-school slapstick and modern short-form video humor.