The discharge of blood mixed with pieces of cellular tissue from the uterus out through the vagina, which occurs roughly every month in uninseminated women; menstrual flow.
The periodic discharging of the menses, the flow of blood and cells from the lining of the uterus in unfertilized females of humans and other primates.
An instance of menstruation, the part of each month during which a fertile woman menstruates.