fer·​mi·​on ˈfer-mē-ˌän How to pronounce fermion (audio)
: a particle (such as an electron, proton, or neutron) whose spin quantum number is an odd multiple of ¹/₂ compare boson
fermionic adjective

Examples of fermion in a Sentence

Recent Examples on the Web Supersymmetry hypothesizes an as-yet-undiscovered boson partner for every fermion, and a fermion partner for each boson. Kenneth Chang, New York Times, 10 May 2023 If a fermion orbits another fermion, its quantum state remains unchanged. Stephen Ornes, Discover Magazine, 12 Dec. 2020 Familiar constituents of matter like electrons and quarks fall into the group known as fermions; while those that carry fundamental forces like photons, the particles of light that convey the force of electromagnetism, are known as bosons. Kenneth Chang, New York Times, 10 May 2023 This idea bridges two categories of particles—bosons, which can be packed together in large numbers, and fermions, which are antisocial and will share space only with particles of opposite spin. Marcela Carena, Scientific American, 1 Oct. 2021 Consider the Weyl fermion. Devin Powell, Discover Magazine, 20 Mar. 2019 Those blocks can be divided into two basic clans: fermions and bosons. Jennifer Ouellette, Ars Technica, 24 Mar. 2023 In this case, the horizontal axis is a scalar mass parameter, and the vertical axis is a fermion mass parameter, in terms of which everything else is determined (within this highly constrained and frankly unrealistic parameterization). Sean Carroll, Discover Magazine, 17 Feb. 2011 Physicists are also reassessing particle flavor, a quantum property that defines the species of fermion: up quark, down quark, electron, muon, and so on. Daniel Garisto, Scientific American, 8 Sep. 2022 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fermion.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Enrico Fermi + English -on entry 2

First Known Use

1947, in the meaning defined above

Time Traveler
The first known use of fermion was in 1947

Dictionary Entries Near fermion

Cite this Entry

“Fermion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fermion. Accessed 2 Oct. 2023.

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