Proliferation is the growth of tissue cells. In many diseases, it is abnormal. Cancer cells are very prolific. They have high rates of cell division and growth.
Hall JE. Genetic control of protein synthesis, cell function, and cell reproduction. In: Hall JE, ed. Guyton and Hall Textbook of Medical Physiology. 13th ed. Philadelphia, PA: Elsevier; 2016:chap 3.