| Noun | 1. | menstruation - 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"--Aristotlehypermenorrhea, menorrhagia - abnormally heavy or prolonged menstruation; can be a symptom of uterine tumors and can lead to anemia if prolonged | |