It is any hole or opening on the body's surface that leads to the considered cavity: such as the mouth, nose, ear, anus, woman's private part, the 'ama (a head wound), the 'jaifa (a wound in the abdomen), and the hole, if it leads to the considered cavity. Fasting is not invalidated except by what reaches the considered cavity through a considered orifice, as mentioned in Bada'i al-Sana'i 2: 93.