1) The science of high energy radiation and of the sources and the chemical, physical, and biologic effects of such radiation; the term usually refers to the diagnosis and treatment of disease. 2) The scientific discipline of medical imaging using ionizing radiation, radionuclides, nuclear magnetic resonance, and ultrasound.
Branch of medicine that deals with the use of radiant energy including X rays, gamma rays, radiowaves, high frequency sound waves in the diagnosis and treatment of disease.