ovarian benign neoplasm (Monarch Disease Ontology entry MONDO_0000646) is a non-metastasizing neoplasm that arises from the ovary. Representative examples include serous cystadenoma, mucinous cystadenoma, clear cell adenofibroma, benign Brenner tumor, thecoma, and fibroma. Also known as: benign neoplasm of ovary, benign neoplasm of the ovary, benign ovarian neoplasm, benign ovarian tumor, benign ovarian tumour, benign tumor of ovary, benign tumor of the ovary, benign tumour of ovary.