from The American Heritage® Dictionary of the English Language, 4th Edition
- n. 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.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A small, bronze Judean coin from the 1st century BC. The lowest value coin ever in circulation. Considered by some to be the widow's mite.
- n. An elementary particle with a spin of 1/2 (a fermion) which is immune to the strong nuclear force (including the electron, the muon, the neutrino and the tauon).
from the GNU version of the Collaborative International Dictionary of English
- 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.
from The Century Dictionary and Cyclopedia
- n. The smallest coin of modern Greece, equal to a centime. One hundred lepta make a drachma.
- n. The typical genus of Leptonidæ.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. an elementary particle that participates in weak interactions; has a baryon number of 0
- n. 100 lepta equal 1 drachma in Greece
lepto- + -on1.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Ancient Greek λεπτόν (lepton), neuter form of λεπτός (leptos, "small"). (Wiktionary)