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 In 2021 the collaboration measured the muon’s magnetic moment to a precision of one part in two million. Daniel Garisto, Scientific American, 10 Aug. 2023 Still, scientists readily encounter muons in the wild. Rahul Rao, Popular Science, 17 Aug. 2023 And a muon is basically like a really big electron. Jackie Appel, Popular Mechanics, 15 Aug. 2023 The denser the imaged object, the more muons are blocked, casting a telltale shadow. Jennifer Ouellette, Ars Technica, 2 Mar. 2023 The blue line shows the reconstructed track of the muon, and the red arrow denotes the energy of the undetected muon neutrino. Jennifer Ouellette, Ars Technica, 24 Mar. 2023 Now, almost 8 years later, researchers from Fermilab have announced the first results from that experiment: a tiny subatomic particle called a muon is breaking the fundamental rules of the Standard Model of particle physics and upending our understanding of the universe. William Herkewitz, Popular Mechanics, 7 Apr. 2021 This term describes how strongly a muon interacts with a magnetic field. Andreas Crivellin, Scientific American, 23 Oct. 2022 Enlarge / Event display of a W-boson candidate decaying into a muon and a muon neutrino inside the ATLAS experiment. Jennifer Ouellette, Ars Technica, 24 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'muon.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

Dictionary Entries Near muon

Cite this Entry

“Muon.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2023.

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