A benign or malignant, gonadal or extragonadal neoplasm that originates from germ cells. Representative examples include teratoma, seminoma, embryonal carcinoma, and yolk sac tumor. The disease is germ cell tumor (MONDO_0005040). Also known as: germ cell neoplasm, neoplasm of germ cell, neoplasm of the germ cell, tumor of germ cell, tumor of the germ cell, tumour of germ cell, tumour of the germ cell.