vagina /vəjī″nə/ [L, sheath] , the part of the female genitalia that forms a canal from the orifice through the vestibule to the uterine cervix. It is behind the bladder and urethra and in front of the rectum. In the adult woman the anterior wall of the vagina is about 7 cm long, and the posterior wall is about 9 cm long. The canal is actually a potential space; the walls usually touch. The muscles of the vagina are innervated by the pudendal nerve and perfused by the vaginal artery.
