mu·​on | \ ˈmyü-ˌän How to pronounce muon (audio) \

Definition of muon

: 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

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Other Words from muon

muonic \ myü-​ˈä-​nik How to pronounce muonic (audio) \ adjective

Examples of muon in a Sentence

Recent Examples on the Web As a neutrino from Fermilab travels along, its mixture changes, so that a muon neutrino might morph into an electron neutrino or a tau neutrino. Quanta Magazine, "Neutrinos Lead to Unexpected Discovery in Basic Math," 13 Nov. 2019 Or is there something peculiar about how protons interact with muons, compared with their behavior around electrons? Dan Falk, Scientific American, "Ultraprecise Measurement Pinpoints the Proton’s Size," 28 Nov. 2019 Fortunately, the air showers sparked by cosmic rays contain a higher proportion of muons, short-lived cousins of the electrons, than the showers from gamma rays. Dennis Normile, Science | AAAS, "Highest energy light ever seen traced to Crab Nebula," 8 July 2019 The fundamental particles that have so far been identified have been given esoteric names like quarks, leptons, muons and taus. Dylan Loeb Mcclain, New York Times, "Ann Nelson, Expert on Particle Physics, Is Dead at 61," 26 Aug. 2019 There are three types of neutrinos, referred to as the three flavors: electron, muon, and tau neutrinos. David Grossman, Popular Mechanics, "Ghost Particles Could Explain Just About Everything in the Universe," 23 Aug. 2019 Scientists may have discovered one of the oldest Christian churches in the world by using muon radiography to scan a mysterious subterranean building located in the ancient Russian city of Derbent, on the Caspian Sea's coast. Fox News, "Scientists may have found one of the oldest Christian churches in the world," 12 July 2019 Study coauthor Balakrishnan Hariharan devised a model that determined how powerful an electric field would need to be to alter the number of muons detected in GRAPES-3. Adam Mann, National Geographic, "Most powerful electrical storm on record detected," 23 Apr. 2019 The fundamental particles that have so far been identified have been given esoteric names like quarks, leptons, muons, and taus. Dylan Loeb Mcclain,, "Ann Nelson, expert on particle physics, 61," 29 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'muon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of muon

1951, in the meaning defined above

History and Etymology for muon

contraction of earlier mu-meson, from mu

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Statistics for muon

Last Updated

25 Dec 2019

Cite this Entry

“Muon.” The Dictionary, Merriam-Webster Inc., Accessed 26 January 2020.

More from Merriam-Webster on muon

Rhyming Dictionary: Words that rhyme with muon Encyclopedia article about muon

Comments on muon

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to express in a more acceptable way

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