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 adjective

Examples of fermion in a Sentence

Recent Examples on the Web
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Antimatter isn’t counted separately but rather is included in each fermion field’s 5.5 degrees of freedom. Quanta Magazine, 15 June 2026 The material, known as uranium ditelluride (or UTe2), is an unconventional heavy-fermion superconductor. Georgina Jedikovska, Interesting Engineering, 8 May 2026 Six quarks, six leptons, and antiparticles comprise the fermions. Big Think, 27 Apr. 2026 Still, the team says their fermion dark matter model can account for this. Robert Lea, Space.com, 12 Feb. 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

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Cite this Entry

“Fermion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fermion. Accessed 24 Jun. 2026.

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