electromagnetic wave

wave of radiation from the electromagnetic spectrum

Electromagnetic (EM) radiation is a self-propagating wave in space with electric and magnetic components. These components oscillate at right angles to each other and to the direction of propagation, and are in phase with each other. Electromagnetic radiation is classified into types according to the frequency of the wave: these types include, in order of increasing frequency, radio waves, microwaves, terahertz radiation, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
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Noun
1. radiation consisting of waves of energy associated with electric and magnetic fields resulting from the acceleration of an electric charge
(synonym) electromagnetic radiation, nonparticulate radiation
(hypernym) radiation
(hyponym) actinic radiation, actinic ray
(part-meronym) photon

A wave produced by the interaction of time-varying electric and magnetic fields.

 Say it 
A wave that involves perpendicular oscillations in the electric and magnetic fields, moving at a speed of 2.99792458×108 m/s in a vacuum away from the source. gamma rays , x-rays , ultraviolet light , visible light , infrared radiation ,and radio waves are all electromagnetic waves.