Definition of: X-rays

(eks′rāz′) noun plural
Electromagnetic radiations of extremely short wavelength, emitted from a substance when it is bombarded by a stream of electrons moving at a sufficiently high velocity, as in a Coolidge tube. Their great penetrating power, ionizing effect, and property of acting on photographic plates have many useful applications, especially in the detection, diagnosis, and treatment of certain organic disorders, chiefly internal. Also called Roentgen rays. [Trans. of G X-strahlen, name coined by Roentgen, their discoverer, because their nature was unknown]