[men.stru.a.tion] n (ca. 1784): a discharging of blood, secretions, and tissue debris from the uterus that recurs in nonpregnant breeding-age primate females 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 6c
MENSTRUATION
Meaning of MENSTRUATION in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012