Word Study
lepton
CIDE DICTIONARY
lepton, n.
an elementary particle that participates in weak interactions but does not participate in the strong interaction; it has a baryon number of 0. Some known leptons are the electron , the negative muon , the tau-minus particle , and the neutrinos associated with each of these particles. [WordNet 1.5]
OXFORD DICTIONARY
lepton, n. (pl. lepta) a Greek coin worth one-hundredth of a drachma.
lepton, n. (pl. leptons) Physics any of a class of elementary particles which do not undergo strong interaction, e.g. an electron, muon, or neutrino.
Etymology
LEPTO- + -ON
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