A benign, borderline, or malignant epithelial tumor of the ovary characterized by the presence of neoplastic epithelial cells that contain intracytoplasmic mucin and may resemble the epithelial cells of the endocervix or gastrointestinal tract. The disease is ovarian mucinous neoplasm (MONDO_0003756). Also known as: mucinous neoplasm of ovary, mucinous neoplasm of the ovary, mucinous tumor of ovary, mucinous tumor of the ovary, mucinous tumour of ovary, mucinous tumour of the ovary, ovarian mucinous tumor, ovarian mucinous tumour.