seminoma /sem′inō″mə/ pl. seminomas, seminomata [L, semen + oma, tumor] , a malignant tumor of the testis. It is the most common testicular tumor and is believed to arise from the seminiferous epithelium of the mature or maturing testis. The two types are classic, or typical, and spermatocytic; anaplastic seminoma is a variant of the classic type. Compare dysgerminoma.
