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 muon (audio) \ adjective

Examples of muon in a Sentence

Recent Examples on the Web In tantalizing results dating back to 2001, g-2 found that the muon is slightly more magnetic than theory predicts. Adrian Cho, Science | AAAS, "The cloak-and-dagger tale behind this year’s most anticipated result in particle physics," 27 Jan. 2021 By giving a neutrino of its own to both the electron and the muon, the pairing up helped show how to organize and account for the growing table of elementary particles. Washington Post, "Jack Steinberger, Nobel laureate in physics, dies at 99," 17 Dec. 2020 Unfortunately for physicists looking to depart from the predictions of the Standard Model, the muon seems to get its mass from the same place as the tau. Daniel Garisto, Scientific American, "Higgs Boson Gives Next-Generation Particle Its Heft," 6 Aug. 2020 Previously, evidence the Higgs ever decayed into two muons was so weak that theorists’ efforts to come up with models in which the muon got its mass elsewhere were perfectly justified. Daniel Garisto, Scientific American, "Higgs Boson Gives Next-Generation Particle Its Heft," 6 Aug. 2020 The electron, muon and tau flavors would all be observable, at least in principle. William Charles Louis, Scientific American, "Hidden Neutrino Particles May Be a Link to the Dark Sector," 1 July 2020 Neutrinos come in three flavors, essentially: electron neutrinos, muon neutrinos and tau neutrinos. Ashley Strickland, CNN, "Scientists didn't detect a parallel universe in Antarctica. But they are learning more about mysterious, ghostly neutrinos," 27 May 2020 These include the familiar electron, along with its heavier relatives, the muon and tau (each of which has antimatter counterparts), along with three corresponding types of neutrinos and anti-neutrinos. John Timmer, Ars Technica, "Neutrinos may help us understand how matter prevailed over antimatter," 15 Apr. 2020 Since 2014, NOνA researchers have fired muon neutrinos from Fermi National Accelerator Laboratory (Fermilab) to a detector 810 kilometers away in Ash River, Minnesota. Adrian Cho, Science | AAAS, "Skewed neutrino behavior could help explain matter’s dominion over antimatter," 15 Apr. 2020

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

4 Feb 2021

Cite this Entry

“Muon.” Dictionary, Merriam-Webster, Accessed 27 Feb. 2021.

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