germ cell tumor
any of a group of tumors arising from primitive germ cells, usually of the testis or ovary; they range from benign to highly malignant. Types include embryonal carcinoma, germinoma, gonadoblastoma, polyembryoma, teratoma, and yolk sac or endodermal sinus tumor, as well as some types of choriocarcinoma. Many tumors are mixtures of types.
Medical dictionary.
2011.