Proliferation is the growth of tissue cells. In many diseases, it is abnormal. Cancer cells are very prolific. They have higher than normal rates of cell division and growth.
Hall JE, Hall ME. Genetic control of protein synthesis, cell function, and cell reproduction. In: Hall JE, Hall ME eds. Guyton and Hall Textbook of Medical Physiology. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 3.