background radiation


: the microwave radiation pervading the universe that exhibits a corresponding blackbody temperature of 2.7 K and that is the principal evidence supporting the big bang theory

called also cosmic background radiation

Examples of background radiation in a Sentence

Recent Examples on the Web We're constantly exposed to background radiation just by living on Earth. Rhett Allain, WIRED, 23 Feb. 2024 These actions not only harmed the soldiers themselves but also caused a significant surge in background radiation levels within the vicinity. Monique Brouillette, Popular Mechanics, 28 Aug. 2023 In research published in 2018, scientists studied the cells of bank voles that inhabit the Chernobyl nuclear power plant, where background radiation levels are 100 times greater than in uncontaminated areas. Monique Brouillette, Popular Mechanics, 6 July 2023 Noticing when decay results in electrons but not neutrinos can be difficult, especially because neutrinos are plentiful everywhere—billions pass through your body every second—and are often produced when background radiation reacts with machine components. Joanna Thompson, Scientific American, 1 July 2022 In the decades since, astronomers have learned there’s much more to the unseen universe, finding background radiation at practically every wavelength observed. Steve Nadis, Discover Magazine, 31 May 2018 The experimenters need to establish that the detector is recording dark matter—not just background radiation. Lisa Randall, Discover Magazine, 21 Feb. 2012 The skies gave willingly: the signature of microwave background radiation, left over from the Big Bang; Cygnus X-1, the first discovered black hole; the existence of exoplanets. Samanth Subramanian, The New Republic, 6 Apr. 2021 Citing Rosatom, TASS reported that the objects create 90% of the background radiation in the Russian Arctic. Fox News, 5 Aug. 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'background radiation.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1968, in the meaning defined above

Time Traveler
The first known use of background radiation was in 1968

Dictionary Entries Near background radiation

Cite this Entry

“Background radiation.” Dictionary, Merriam-Webster, Accessed 21 Apr. 2024.

Last Updated: - Updated example sentences
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