A non-neoplastic disorder characterized by the growth of endometrial tissue in the ovaries. It results in the development of blood filled ovarian cysts (chocolate cysts), and creation of scars and adhesions. The disease is Monarch Disease Ontology entry MONDO_0006337 (ovarian endometriosis). Also known as: endometriosis (disease) of ovary, endometriosis of ovary, ovary endometriosis (disease).