background radiation

noun

: 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
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By comparison, a person on Earth receives an average of 2 mSv every year from just background radiation, NASA said. Mary Kekatos, ABC News, 5 Sep. 2024 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 See all Example Sentences for background radiation 

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.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/background%20radiation. Accessed 22 Nov. 2024.

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