Perineum: The area between the anus and the scrotum in the male and between the anus and the vulva (the labial opening to the vagina) in the female.An episiotomy is a surgical procedure to widen the outlet of the birth canal to facilitate delivery of the baby and avoid a jagged rip of the perineum.erineum: The area between the anus and the scrotum in the male and between the anus and the vulva (the labial opening to the vagina) in the female.