Noun | 1. | lymphoma - a neoplasm of lymph tissue that is usually malignant; one of the four major types of cancer cancer, malignant neoplastic disease - any malignant growth or tumor caused by abnormal and uncontrolled cell division; it may spread to other parts of the body through the lymphatic system or the blood stream Hodgkin's disease - a malignant disorder in which there is progressive (but painless) enlargement of lymph tissue followed by enlargement of the spleen and liver |