- An international unit of X-radiation or gamma-radiation. (A roentgen is abbreviated R). Named for Wilhelm Roentgen who greatly expanded our diagnostic and treatment capabilities by discovering radiology. A German professor of physics, Roentgen wanted to prove his hypothesis that cathode rays could penetrate substances besides air. When he saw that he could film his thumb and forefinger and their bones on a screen, the story goes that he replaced the screen with a photographic plate and X-rayed his wife's hand. Roentgen's report of his findings, "On a New Kind of Rays," was published by the Physical-Medical Society of Würzburg in December 1895.
* * *Wilhelm K., German physicist and Nobel laureate, 1845–1923. Discovered x-rays in November, 1895; awarded Nobel Prize in Physics in 1901 for his discovery. See r., r. ray.
* * *roent·gen also rönt·gen 'rent-gən, 'rənt-, -jən; 'ren-chən, 'rən- adj of, relating to, or using X-rays: x-ray <\roentgen examinations> <\roentgen therapy>Rönt·gen or Roent·gen 'rœnt-gən Wilhelm Conrad (1845-1923)German physicist. Röntgen is famous for his discovery of X-rays in 1895. He made the discovery while experimenting with electric current flow in a cathode-ray tube. He observed that a nearby piece of the platinocyanide of barium gave off light when the tube was in operation. He attributed the fluorescence of the chemical to some unknown form of radiation. Because of the uncertain nature of the radiation he called the phenomenon X radiation. For his discovery of X-rays he was awarded the Nobel Prize for Physics in 1901. His discovery had a great impact on both physics and medicine.roentgen also röntgen n the international unit of x-radiation or gamma radiation equal to the amount of radiation that produces in one cubic centimeter of dry air at 0°C (32°F) and standard atmospheric pressure ionization of either sign equal to one electrostatic unit of charge
* * *n.a unit of exposure dose of X- or gamma-radiation equal to the dose that will produce 2.58 x 10-4 coulomb on all the ions of one sign, when all the electrons released in a volume of air of mass 1 kilogram are completely stopped.
* * *Roent·gen (rentґgən) see RÑ†ntgen.
Medical dictionary. 2011.