cosmic ray

noun

: a stream of atomic nuclei of extremely penetrating character that enter the earth's atmosphere from outer space at speeds approaching that of light

Examples of cosmic ray in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In that case, a cosmic ray is thought to have caused a slight flip in the electronic voting system, incorrectly adding votes to the tally. Stefanie Waldek, Space.com, 6 Mar. 2025 This, in turn, affects convection in the outer core—the dynamo-like process that generates the magnetic field that protects life on Earth from harmful cosmic rays. Gordon G. Chang, Newsweek, 3 Mar. 2025 From simulations of the supernova, the researchers found that Earth suffered from cosmic rays for 100,000 years. Jamie Carter, Forbes, 27 Feb. 2025 The space agency said Wednesday an instrument on Voyager 2 that measures charged particles and cosmic rays will shut off later this month. Compiled By Democrat-Gazette Staff From Wire Reports, arkansasonline.com, 6 Mar. 2025 See All Example Sentences for cosmic ray

Word History

First Known Use

1925, in the meaning defined above

Time Traveler
The first known use of cosmic ray was in 1925

Cite this Entry

“Cosmic ray.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cosmic%20ray. Accessed 23 Mar. 2025.

Kids Definition

cosmic ray

noun
: a stream of atomic nuclei of extremely penetrating character that enter the earth's atmosphere from outer space at speeds approaching that of light

More from Merriam-Webster on cosmic ray

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!