radio-, radi-, rad-

(Latin: ray, radiating [the Latin word for the spokes of a wheel is radius]; spoke, staff, rod)

radiocardiography
The technique of recording or interpreting radiocardiograms or a graphic record of the concentration of injected radioisotope (a chemical element) within the cardiac chambers.
radiodermatitis
radiodontist
radiograph
A photographic image produced on a radiosensitive surface by radiation other than visible light; especially, by X-rays or gamma rays.
radiologist
radiology
radiolucent
Transparent to X-rays.
radiometer
radiomicrometer
radionecrosis
Death caused by excessive exposure to ionizing radiation (x-ray or gamma rays).
radiophobia
An excessive fear of X-rays.
radiophone
1. An instrument for the production of sound by intermittent radiant energy, such as light or heat; the photophone and thermophone are special forms.
2. Radiophone may also be a radio-telephone.
radioplastic
radiopraxis (s), radiopraxes (pl) (nouns)
The medical treatment of diseases with forms of electromagnetic radiation: "Some therapeutic procedures for cancer patients have included radiopraxis or X-rays and other forms of radiation."
radioscope
1. An instrument; such as, a fluoroscope, capable of detecting radiant energy.
2. An instrument that detects radioactivity.