Menstruation

The discharge of the menses; also, the state or the period of menstruating.

the monthly discharge of blood from the uterus of nonpregnant women from puberty to menopause; "the women were sickly and subject to excessive menstruation"; "a woman does not take the gout unless her menses be stopped" - Hippocrates; "the semen begins to appear in males and to be emitted at the same time of life that the catamenia begin to flow in females" - Aristotle