muon

noun

mu·​on ˈmyü-ˌän How to pronounce muon (audio)
: an unstable lepton that is common in the cosmic radiation near the earth's surface, has a mass about 207 times the mass of the electron, and exists in negative and positive forms
muonic adjective

Examples of muon in a Sentence

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The team is now exploring the feasibility of using muons, one of the fundamental subatomic particles, in a future high-energy muon collider. Georgina Jedikovska, Interesting Engineering, 3 Mar. 2026 The only viable explanation is that an even higher-energy particle — a more stable one — must have struck the upper atmosphere of the Earth and produced a particle shower, where those decaying particles led to the presence of these muons. Big Think, 30 Jan. 2026 The facility will produce a lot of tau particles and charm quarks, partly to study whether taus ever shape-shift into muons or electrons. Quanta Magazine, 26 Jan. 2026 Cosmic rays batter Earth's atmosphere constantly, interacting with molecules of air and producing showers of exotic particles such as muons, high energy neutrons and positrons. Tereza Pultarova, Space.com, 3 Dec. 2025 See All Example Sentences for muon

Word History

Etymology

contraction of earlier mu-meson, from mu

First Known Use

1951, in the meaning defined above

Time Traveler
The first known use of muon was in 1951

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Cite this Entry

“Muon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/muon. Accessed 6 Mar. 2026.

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