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[myoo-on] /ˈmyu ɒn/
noun, Physics.
a lepton similar in most respects to the electron except that it is unstable, it may be positively charged, and its mass is approximately 207 times greater; the positively charged muon is the antiparticle of the negatively charged muon. Symbol: μ.
Origin of muon
1950-55; by shortening of mu meson; see mu, -on1
Related forms
muonic, adjective Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for muon
  • They wrongly claim that from muon's perspective, the sea level approaches muon travelling the contracted length.
  • Pohl and his team have a come up with a smaller number by using a cousin of the electron, known as the muon.
  • As with muon-catalyzed fusion, reality does not automatically translate to practical application.
  • So, the signature to look for when searching for top quarks is: one muon, one neutrino and four jets.
  • Neutrinos come in three varieties: muon, tau, and electron.
  • These particles come in three types or flavours: electron, muon and tau neutrinos.
  • Occasional collisions between neutrinos and ice create a particle called a muon that gives off a slight blue light.
  • Also, from a sub-atomic basis, muon and tau should be measured.
  • Scientists around the world are developing the technologies necessary for a muon accelerator.
  • Development of high intense surface muon beam using a large solid angle axial focusing channel.
British Dictionary definitions for muon


a positive or negative elementary particle with a mass 207 times that of an electron and spin 1/2. It was originally called the mu meson but is now classified as a lepton
Derived Forms
muonic (mjuːˈɒnɪk) adjective
Word Origin
C20: short for mu meson
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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muon in Science
An elementary particle in the lepton family having a mass 209 times that of the electron, a negative electric charge, and a mean lifetime of 2.2 × 10-6 seconds. The muon was originally called the mu-meson and was once thought to be a meson. See Table at subatomic particle.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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