Endometriosis

noun

1. A condition, usually resulting in pain and dysmenorrhea, that is characterized by the abnormal occurrence of functional endometrial tissue outside the uterus.
2. A condition in which the endometrium is found elsewhere than in the lining of the uterus.
3. the presence of endometrium elsewhere than in the lining of the uterus; causes premenstrual pain and dysmenorrhea