electromagnetic radiation

noun

|Updated on: 20 Jun 2018

Definition of electromagnetic radiation

: energy in the form of electromagnetic waves; also : a series of electromagnetic waves

See electromagnetic radiation defined for kids

Recent Examples of electromagnetic radiation from the Web

By 375,000 years after the Big Bang, the temperature had fallen to 5,400 degrees Fahrenheit and the universe became transparent, freeing visible light and other forms of electromagnetic radiation to travel across the cosmos.

— dan falk /, NBC News, "What is the Big Bang theory?," 9 June 2018
Unlike dark matter, ordinary matter heats up when squeezed, generating light and other electromagnetic radiation that then pushes the matter around.

— adrian cho, Science | AAAS, "Galaxy simulations are at last matching reality—and producing surprising insights into cosmic evolution," 30 May 2018
These devices are not really clocks at all in the traditional sense, but rather particle physics experiments that are designed to find the specific frequency of electromagnetic radiation that causes a cesium atom's outer electron to transition.

— jay bennett, Popular Mechanics, "The Centuries-Long Quest to Measure One Second," 24 Mar. 2017
Pacific Power says the data the meters transmit is protected and that the radio transmitters generate less electromagnetic radiation than a cellphone.

— donald w. meyers, The Seattle Times, "‘Smart’ meters in Washington state: Convenience or potential invasion of privacy?," 13 May 2018
Northern Mecklenburg County has seen toxic releases to air and water, asbestos contamination and electromagnetic radiation from power lines.

— bruce henderson, charlotteobserver, "Mysterious eye cancer that baffled Huntersville is now cropping up two states away | Charlotte Observer," 18 Apr. 2018
While a traditional dry sauna simply heats the surrounding air to around 190 degrees, far infrared saunas use infrared lamps to release electromagnetic radiation, which can be absorbed by the body as much as 1.5 inches under the skin.

— jamie lisanti, SI.com, "Far Infrared Saunas: Explaining the Latest Trend in Athlete Recovery," 9 Apr. 2018
Below the device, a 400-megahertz pulse of electromagnetic radiation continually sweeps the earth.

— peter brannen, Washington Post, "A search of James Madison’s Virginia estate uncovers evidence of slaves who lived on his land," 2 Jan. 2018
Radio-frequency energy is non-ionizing electromagnetic radiation, which doesn’t have enough energy to remove electrons from atoms.

— ars technica, SELF, "Here’s How to Handle Unfounded Fears About Cell Phones Causing Cancer," 19 Dec. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'electromagnetic radiation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.