Definition of "lepton" [lepton]

• Any of a family of elementary particles that participate in the weak interaction, including the electron, the muon, and their associated neutrinos. See Table at subatomic particle. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The best known lepton is the electron; the other five are the muon, the tau particle, and three matching neutrinos."
• "The coin was called a lepton and it took one hundred of them to make a denarius—an average day’s wage for a laborer."
• "Contraction of minute, from the Latin minutum, the translation of the Greek word lepton, the very smallest bronze of copper coin (Luke 12: 59; 21: 2)."