meson

American  

[mee-zon, ‑son, mez-on, mes‑] / ˈmi zɒn, ‑sɒn, ˈmɛz ɒn, ˈmɛs‑ /

noun

1. Physics. any hadron, or strongly interacting particle, other than a baryon. Mesons are bosons, having spins of 0, 1, 2, …, and, unlike baryons, do not obey a conservation law.

---

meson British  

/ ˈmiːzɒn /

noun

1. Former name: mesotron.  any of a group of elementary particles, such as a pion or kaon, that usually has a rest mass between those of an electron and a proton, and an integral spin. They are responsible for the force between nucleons in the atomic nucleus See also muon

---

meson Scientific  

/ mĕz′ŏn′,mĕs′-,mē′zŏn′,-sŏn′ /

1. Any of a family of subatomic particles that are composed of a quark and an antiquark. Their masses are generally intermediate between leptons and baryons, and they can have positive, negative, or neutral charge. Mesons form a subclass of hadrons and include the kaon, pion and J/psi particles. Mesons were originally believed to be the particles that mediated the strong nuclear force, but it has since been shown that the gluon mediates this force.

2. See Table at subatomic particle

---

meson Cultural  

1. An elementary particle in the atomic nucleus.

---

Other Word Forms

• mesonic
  adjective

Etymology

Origin of meson

1935–40; mes- + -on ¹ ( def. ); cf. mesotron

Example Sentences

The results also suggest that the mass of the η′ meson may decrease when it is inside nuclear matter.

From Science Daily • Apr. 25, 2026

The track she was looking at, later labelled k, was evidence of an unknown particle, now known as the kaon or K meson.

From BBC • Jul. 23, 2024

The Belle II experiment in Japan, which is dedicated to investigating B meson decays, is also gathering new evidence.

From Scientific American • Nov. 14, 2022

But, until now, it hadn’t been seen in a particle that includes the ‘charm’ flavour of quark, such as a D meson.

From Nature • Mar. 26, 2019

Yet through 1947, Lawrence’s attempts to capture an artificially produced meson on photographic film were unavailing.

From "Big Science" by Michael Hiltzik