Roentgen

[rent-guh n, -juh n, ruhnt-; for 1 also German rœnt-guh n] /ˈrɛnt gən, -dʒən, ˈrʌnt-; for 1 also German ˈrœnt gən/
noun
1.
Wilhelm Konrad
[wil-helm kon-rad;; German vil-helm kawn-raht] /ˈwɪl hɛlm ˈkɒn ræd;; German ˈvɪl hɛlm ˈkɔn rɑt/ (Show IPA), 1845–1923, German physicist: discoverer of x-rays 1895; Nobel prize 1901.
2.
(lowercase) Physics. a unit of exposure dose that measures x-rays or gamma rays in terms of the ions or electrons produced in dry air at 0° C and one atmosphere, equal to the amount of radiation producing one electrostatic unit of positive or negative charge per cubic centimeter of air.
Abbreviation: r, R.
adjective
3.
(sometimes lowercase) of or pertaining to Wilhelm Roentgen, the Roentgen unit, or especially to x-rays.
Also, Röntgen.
British Dictionary definitions for Roentgen

roentgen

/ˈrɒntɡən; -tjən; ˈrɛnt-/
noun
1.
a unit of dose of electromagnetic radiation equal to the dose that will produce in air a charge of 0.258 × 10–3 coulomb on all ions of one sign, when all the electrons of both signs liberated in a volume of air of mass one kilogram are stopped completely R, r
Word Origin
C20: named after W. K. Roentgen

Roentgen

/ˈrɒntɡən; -tjən; ˈrɛnt-; German ˈrœntɡən/
noun
1.
Wilhelm Konrad (ˈvɪlhɛlm ˈkɔnraːt). 1845–1923, German physicist, who in 1895 discovered X-rays: Nobel prize for physics 1901
Word Origin and History for Roentgen

roentgen

1896, in Roentgen rays "X-rays," in recognition of German physicist Wilhem Conrad Röntgen (1845-1923), who discovered X-rays in 1895. As a unit of exposure to radiation, it is attested from 1922, proposed in French in 1921.

Roentgen in Medicine

roentgen roent·gen or rönt·gen (rěnt'gən, -jən, rŭnt'-)
n.
Abbr. R, r
A unit of radiation exposure that is equal to the quantity of ionizing radiation that will produce one electrostatic unit of electricity in one cubic centimeter of dry air at 0°C and standard atmospheric pressure.

Roentgen Roent·gen (rěnt'gən, -jən, rŭnt'-) or Rönt·gen (rɶnt'gən), Wilhelm Konrad. 1845-1923.

German physicist who discovered x-rays and developed x-ray photography, revolutionizing medical diagnosis. He won a 1901 Nobel Prize.

Roentgen in Science
Roentgen
  (rěnt'gən, rěnt'jən)   
German physicist who discovered x-rays in 1895 and went on to develop x-ray photography, which revolutionized medical diagnosis. In 1901 he was awarded the Nobel Prize for physics.
Encyclopedia Article for Roentgen

R

unit of X-radiation or gamma radiation, the amount that will produce, under normal conditions of pressure, temperature, and humidity, in 1 kg (2.2 lbs) of air, an amount of positive or negative ionization equal to 2.58104 coulomb. It is named for the German physicist Wilhelm Conrad Rontgen. See also rem.

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