Try Our Apps


Supposedly vs. Supposably


[rent-guh n, -juh n, ruhnt-; for 1 also German rœnt-guh n] /ˈrɛnt gən, -dʒən, ˈrʌnt-; for 1 also German ˈrœnt gən/
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.
(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.
(sometimes lowercase) of or relating to Wilhelm Roentgen, the Roentgen unit, or especially to x-rays.
Also, Röntgen. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
Cite This Source
Examples from the Web for Roentgen
Historical Examples
  • The third are very penetrating rays, which are not deflected by electricity and which are seemingly identical with Roentgen rays.

  • What miracles are wireless telegraphy, flying-machines, the Roentgen ray!

    Unicorns James Huneker
  • Nothing could more vividly bear out this gentleman than contemplation of the possibilities of the Roentgen ray.

    Peeps at People Robert Cortes Holliday
  • We have seen the discovery of the Roentgen Rays born of observation.

    The Montessori Method Maria Montessori
  • It is with such a supply of electricity conducted through a vacuum tube that the cathode ray and the Roentgen ray are produced.

  • Luckily, not even Roentgen rays could discover what a store of drawings, charts, and fortress plans I keep in my memory.

  • "That light wasn't exactly the Roentgen variety," Drake interrupted my absorption in our surroundings.

    The Metal Monster A. Merritt
  • Is it credible that old Melchizedek knew nothing about the telephone, or the Roentgen ray, or the cholera bacillus?

  • Call it the X-poison, if you will, as Roentgen did with his unknown ray.

    The Treatment of Hay Fever George Frederick Laidlaw
  • At one time it was psychic force, then Roentgen or X-rays; lately it has been attributed to the mysterious effects of radium!

British Dictionary definitions for Roentgen


/ˈrɒntɡən; -tjən; ˈrɛnt-/
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


/ˈrɒntɡən; -tjən; ˈrɛnt-; German ˈrœntɡən/
Wilhelm Konrad (ˈvɪlhɛlm ˈkɔnraːt). 1845–1923, German physicist, who in 1895 discovered X-rays: Nobel prize for physics 1901
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for 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.

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
Roentgen in Medicine

roentgen roent·gen or rönt·gen (rěnt'gən, -jən, rŭnt'-)
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.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
Roentgen in Science
  (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.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source

Word of the Day

Difficulty index for Roentgen

Few English speakers likely know this word

Word Value for Roentgen

Scrabble Words With Friends

Nearby words for roentgen