NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,777 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
Radiation that has both electric and magnetic fields and travels in waves. It comes from natural and man-made sources. EMR can vary in strength from low energy to high energy. It includes radio waves, microwaves, infrared light, visible light, ultraviolet light, x-rays, and gamma rays. Also called electromagnetic radiation.