nounPlural lepta ˈlɛptɒnˈlɛptɑn
A former monetary unit of Greece used only in calculations, worth one hundredth of a drachma.
Origin
  
From Greek lepton, neuter of leptos 'small'.
nounPlural lepta ˈlɛptɒnˈlɛptɑn
Physics A subatomic particle, such as an electron, muon, or neutrino, which does not take part in the strong interaction.
 Example sentencesExamples
-  These infinitesimal particles are usually grouped into four main categories: the mesons, the baryons, the leptons, and the photons (the most basic unit of electromagnetic radiation).
 -  Quarks and charged leptons also feel the electromagnetic force, and quarks feel the strong force.
 -  Finally, the EM force acts on electrically charged particles: charged leptons (like electrons), and charged force carriers.
 -  Like quarks and leptons, the Higgs particle also derives its mass from coupling to the Higgs condensate.
 -  There are small subatomic particles called leptons.
 
Derivatives
  
adjective 
Physics  No observation of leptonic decays of D-mesons has yet been reported, owing to the smaller branching fraction.
 Example sentencesExamples
-  This colour quantum number is additional to leptonic flavour which distinguishes neutrinos from charged leptons.
 
Origin
  
1940s: from Greek leptos 'small' + -on.