\ˌmen(t)-strə-ˈwā-shən, men-ˈstrā-\

Definition of MENSTRUATION

: a discharging of blood, secretions, and tissue debris from the uterus that recurs in nonpregnant human and other primate females of breeding age at approximately monthly intervals and that is considered to represent a readjustment of the uterus to the nonpregnant state following proliferative changes accompanying the preceding ovulation; also : period 1b

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