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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Physicists at the Max Planck Institute of Quantum Optics used muonic hydrogen, replacing the electron orbiting the nucleus with a muon, the electron’s heavier (and very short-lived) sibling. ArsTechnica, 14 Apr. 2026 By carefully measuring the energy and momentum of muons produced in about 100 million collisions thought to have created W bosons, the physicists arrived at their new mass estimate. Clara Moskowitz, Scientific American, 10 Apr. 2026 From 1993 to 1998, an experiment at Los Alamos National Laboratory called the Liquid Scintillator Neutrino Detector, or LSND, saw what looked like too many electron neutrinos in a beam of mostly muon neutrinos. Quanta Magazine, 8 Apr. 2026 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 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 21 Apr. 2026.

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