fermion

noun

fer·​mi·​on ˈfer-mē-ˌän How to pronounce fermion (audio)
ˈfər-
: a particle (such as an electron, proton, or neutron) whose spin quantum number is an odd multiple of ½ compare boson
fermionic
ˌfer-mē-ˈä-nik How to pronounce fermion (audio)
ˌfər-
adjective

Examples of fermion in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Still, the team says their fermion dark matter model can account for this. — Robert Lea, Space.com, 12 Feb. 2026 When packed together, fermions cannot be compressed past a certain point. — Shalma Wegsman, Wired News, 25 May 2025 Six quarks, six leptons, and antiparticles comprise the fermions. — Big Think, 27 Apr. 2026 The material, known as uranium ditelluride (or UTe2), is an unconventional heavy-fermion superconductor. — Georgina Jedikovska, Interesting Engineering, 8 May 2026 See All Example Sentences for fermion

Word History

Etymology

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

Browse Nearby Words

Fermi level
fermion
Fermi surface
See all Nearby Words

Cite this Entry

“Fermion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fermion. Accessed 7 Jul. 2026.

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More from Merriam-Webster on fermion

Britannica.com: Encyclopedia article about fermion

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