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.
As Lee and Kirby did with cosmic rays for the origin of the Fantastic Four, the legendary creators plucked the term gamma rays from real-world science. Robert Lea, Space.com, 12 Feb. 2025 Understanding where these particles come from could reveal more about the origin of mysterious cosmic rays, long thought to be the primary source of neutrinos when the rays strike Earth’s atmosphere. Ashley Strickland, CNN, 12 Feb. 2025 According to their start in the comics, an experimental space flight exposes them to cosmic rays, giving each of the four members incredible abilities. Anders Fogh Rasmussen, Newsweek, 4 Feb. 2025 The probe is now transmitting data about the interstellar medium, including information about cosmic rays, magnetic fields, and particle densities. Thomas G. Moukawsher, Newsweek, 29 Nov. 2024 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

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Cite this Entry

“Cosmic ray.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cosmic%20ray. Accessed 27 Feb. 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

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