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also rönt·gen  (rĕnt′gən, -jən, rŭnt′-)
n. Abbr. R or r
A unit of radiation exposure 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.

[After Wilhelm Conrad Roentgen.]

roent′gen adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.




(Biography) Wilhelm Konrad (ˈvɪlhɛlm ˈkɔnraːt). 1845–1923, German physicist, who in 1895 discovered X-rays: Nobel prize for physics 1901


(ˈrɒntɡən; -tjən; ˈrɛnt-) or


(Units) 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. Symbol: R or r
[C20: named after W. K. Roentgen]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


or Rönt•gen

(ˈrɛnt gən, -dʒən, ˈrʌnt-)

1. Wilhelm Konrad, 1845–1923, German physicist.
2. (l.c.) a unit of radiation dosage equal to the amount of ionizing radiation required to produce one electrostatic unit of charge per cubic centimeter of air. Abbr.: r, R
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


A unit of exposure dose of gamma (or X-) radiation. In field dosimetry, one roentgen is essentially equal to one rad.
Dictionary of Military and Associated Terms. US Department of Defense 2005.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.Roentgen - a unit of radiation exposureroentgen - a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air
radioactivity unit - a measure of radioactivity
2.Roentgen - German physicist who discovered x-rays and developed roentgenography (1845-1923)Roentgen - German physicist who discovered x-rays and developed roentgenography (1845-1923)
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


nRöntgen nt
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
References in periodicals archive ?
1896: German physicist Wilhelm Roentgen gave the first demonstration of X-rays.
1895: Wilhelm Roentgen publishes details of a newly-discovered form of radiation which will become known as X-rays.
1895: Wilhelm Roentgen made the first radiograph, or X-ray - of his wife's hand.
1895 - Wilhelm Conrad Roentgen, German physicist, discovers X-rays.
Paulis is a member of the American Board of Radiology, American Roentgen Ray Society, Society of Breast Imaging and the Monroe County Medical Society.
Among the sections are chest and cardiac, musculoskeletal, brain and spine, ultrasound, fetal, nuclear medicine, and Roentgen classics.
According to a study by American Roentgen Ray Society, rates of false positive breast cancer screening exams fell significantly after complete integration of diagnostic digital breast tomosynthesis (DBT), potentially leading to higher quality, lower costs, and fewer unnecessary biopsies.
The day marks the anniversary of the discovery of X-ray by Wilhelm Roentgen in 1895.
--Short stories: Political Rival, Eulogy, Class, The Corporal's Stories; Photography (1906), Roentgen's Photography (1906);
IN December 1895, German physicist Wilhelm Roentgen discovered a ray, termed X for unknown, which could travel through solid wood or flesh and yield photographs of living people's bones.
Hogg is a member of the ACR; the American Academy of Neurology; the Association of University Radiologists; the Alliance of Medical Student Educators in Radiology; the Alliance of Clinical Educators in Radiology; the Radiological Society of North America; the American Roentgen Ray Society; the American Society of Neuroradiology; the American Society of Head and Neck Radiology; the West Virginia State Medical Association and the Monongalia County Medical Society.
It all began with the chance discovery of X-rays ('X for unknown) by Professor Wilhelm Roentgen in Germany on 8 November 1895.