- Often x-rays.a form of electromagnetic radiation, similar to light but of shorter wavelength and capable of penetrating solids and of ionizing gases.
- such radiation having wavelengths in the range of approximately 0.1–10 nm.
- a radiograph made by x-rays.
- (initial capital letter) a word in communications to represent the letter X.
- to examine, photograph, or treat with x-rays.
- of or relating to x-rays.
Origin of x-ray
1895–1900; translation of German X-Strahl (1895), the name orig. given to the rays by Röntgen, their discoverer, x signifying their unknown nature
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- electromagnetic radiation emitted when matter is bombarded with fast electrons. X-rays have wavelengths shorter than that of ultraviolet radiation, that is less than about 1 × 10 –8 metres. They extend to indefinitely short wavelengths, but below about 1 × 10 –11 metres they are often called gamma radiation
- (as modifier)X-ray astronomy
- a picture produced by exposing photographic film to X-rays: used in medicine as a diagnostic aid as parts of the body, such as bones, absorb X-rays and so appear as opaque areas on the picture
- (usually capital) communications a code word for the letter x
- to photograph (part of the body, etc) using X-rays
- to treat or examine by means of X-rays
C19: partial translation of German X-Strahlen (from Strahl ray), coined by W. K. Roentgen in 1895
Word Origin and History for xray
1896, translation of German X-strahl, from X, algebraic symbol for an unknown quantity, + Strahl (plural Strahlen) "beam, ray." Coined 1895 by German scientist Wilhelm Conrad Röntgen (1845-1923), who discovered them.
Online Etymology Dictionary, © 2010 Douglas Harper
- A relatively high-energy photon with wavelength in the approximate range from 0.01 to 10 nanometers.roentgen ray
- A stream of such photons used for their penetrating power in radiography, radiology, radiotherapy, and scientific research. Often used in the plural.roentgen ray
- A photograph taken with x-rays.
- To irradiate with x-rays.
- To photograph with x-rays.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
- A high-energy stream of electromagnetic radiation having a frequency higher than that of ultraviolet light but less than that of a gamma ray (in the range of approximately 1016 to 1019 hertz). X-rays are absorbed by many forms of matter, including body tissues, and are used in medicine and industry to produce images of internal structures. See more at electromagnetic spectrum.
- An image of an internal structure, such as a body part, taken with x-rays.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Because x-rays can travel through solid material and affect photographic plates, they are widely used in diagnosing medical problems.
Objects in the sky also send out x-rays in processes that use very high energy.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.