Definition of fermion in English:

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Pronunciation: /ˈfermēän/
Pronunciation: /ˈfərmēän/


A subatomic particle, such as a nucleon, that has half-integral spin and follows the statistical description given by Fermi and Dirac.
Example sentences
  • In addition to electrons, the Pauli exclusion principle applies to all sub-atomic particles with half-integral spins, known as fermions, such as neutrons and protons.
  • But if supersymmetry were unbroken, fermions and bosons would be exactly matched in the Universe, and that's not the way things are.
  • Well, what we find experimentally is that the quasiparticles are almost always fermions or bosons.


1940s: from the name of E. Fermi (see Fermi, Enrico) + -on.

For editors and proofreaders

Syllabification: fer·mi·on

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