Menstruation

медицина месячные, регулы

Англо-русский научно-технический словарь

Menstruation

имя существительное [физиология] менструация

Большой англо-русский словарь

Menstruation

noun 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

Энциклопедический словарь Мерриама-Вебстера