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

Recent Examples on the Web
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The muon is the electron’s less stable, 200-times-heavier cousin. Eleni Petrakou, Scientific American, 8 June 2025 When the muon’s inherent magnetism clashes with an external magnetic field, the particle precesses, torquing to and fro like a wobbling, spinning top. Eleni Petrakou, Scientific American, 8 June 2025 The heart of the experiment is a giant 50-foot-diameter magnet, which acts as a racetrack for wobbling muons. Eleni Petrakou, Scientific American, 8 June 2025 No process that occurs on Earth can produce a muon with these sorts of energies. John Timmer, Ars Technica, 12 Feb. 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 11 Jul. 2025.

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