The sound of a cat cooing is the sound produced by the vibration of the cat's false vocal cords. It is usually made when the cat is very comfortable and happy. When the owner strokes the cat and tickles the cat, the cat will happily make this sound, indicating that the cat likes the owner very much. ​​​​​​

The skeleton of the cat's throat is composed of thyroid cartilage and cricoid cartilage. The laryngeal cavity is divided into three parts. The upper part is the laryngeal vestibule, and the trailing edge is the false vocal cord. The cavity between the false vocal cord and the true vocal cord is the larynx. The second and third parts of the cavity are the cavities between the vocal cords and the cartilage ring. The cooing sound is produced by the resonance of the laryngeal cavity when the false vocal cords vibrate.