Mouth, also called oral cavity or buccal cavity, in human anatomy, orifice through which food and air enter the body. The mouth opens to the outside at the lips and empties into the throat at the rear; its boundaries are defined by the lips, cheeks, hard and soft palates, and glottis. It is divided into two sections: the vestibule, the area between the cheeks and the teeth, and the oral cavity proper.


Source: https://www.britannica.com/science/mouth-anatomy