me·​son ˈme-ˌzän How to pronounce meson (audio)
ˈmā-ˌsän How to pronounce meson (audio) ˈmē-ˌzän How to pronounce meson (audio) ˈmē-ˌsän How to pronounce meson (audio)
: any of a group of fundamental particles (such as the pion and kaon) made up of a quark and an antiquark that are subject to the strong force and have zero or an integer number of quantum units of spin
me-ˈzä-nik How to pronounce meson (audio)
mā-ˈsä- How to pronounce meson (audio)
mē-ˈsä- How to pronounce meson (audio)

Examples of meson in a Sentence

Recent Examples on the Web One of these bizarre particles, called the phi meson, sits at the heart of these latest befuddling results. Allison Parshall, Scientific American, 2 Feb. 2023 Two of the products of that decay are an electron and a positron, which can be picked up by detectors, allowing the production of the J/ψ mesons to be registered. John Timmer, Ars Technica, 3 Apr. 2023 Even a small deviation from those one-third odds would indicate that the phi meson’s spin had been influenced by the circling momentum around it. Allison Parshall, Scientific American, 2 Feb. 2023 While transiting the vat, some of the photons will be converted to J/ψ mesons that will then promptly decay. John Timmer, Ars Technica, 3 Apr. 2023 Some of these are another type of meson, kaons. Elizabeth Fernandez, Forbes, 19 Sep. 2021 The Tevatron discovered the top quark, the Bc meson, and the tau neutrino. Daniel Holz, Discover Magazine, 30 Sep. 2011 The Belle II experiment in Japan, which is dedicated to investigating B meson decays, is also gathering new evidence. Andreas Crivellin, Scientific American, 23 Oct. 2022 This new measurement in the B meson system -- indeed, the entire phenomenon of T violation -- has absolutely nothing to do with that arrow of time. Sean Carroll, Discover Magazine, 20 Nov. 2012

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

Word History


International Scientific Vocabulary mes- + -on entry 2

First Known Use

1939, in the meaning defined above

Time Traveler
The first known use of meson was in 1939

Dictionary Entries Near meson

Cite this Entry

“Meson.” Dictionary, Merriam-Webster, Accessed 25 May. 2024.

Kids Definition


: any of a group of elementary particles that act strongly on one another and are among the products of nuclear collisions

Medical Definition


me·​son ˈmez-ˌän How to pronounce meson (audio) ˈmēz- How to pronounce meson (audio)
: any of a group of unstable elementary particles that are subject to nuclear forces and have masses much greater than that of the electron
mesonic adjective

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