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baryon Line breaks: ba¦ryon
Pronunciation: /ˈbarɪɒn/

Definition of baryon in English:


A subatomic particle, such as a nucleon or hyperon, that has a mass equal to or greater than that of a proton.
Example sentences
  • The proton and the neutron are baryons; the electron, the muon, and the neutrino are leptons; whilst the pions are mesons.
  • The strong force is mediated by the gluon (which comes in eight flavors), which binds quarks together to form baryons and mesons and protons and neutrons together to form nuclei.
  • They undergo an enormous Universe-wide phase transformation where all of the quarks and gluons in the Universe become confined together inside mesons such as the pi meson and baryons such as the proton and neutron.


1950s: from Greek barus 'heavy' + -on.



Pronunciation: /barɪˈɒnɪk/
Example sentences
  • The baryonic number, which is equivalent to the atomic mass number, has to remain constant for a reaction.
  • According to our current understanding, after the big bang most of the normal or baryonic material in the universe consisted of the lightest two elements, hydrogen and helium, with only trace amounts of lithium and beryllium.
  • Astronomers can derive the matter density - that is the sum of the baryonic and dark-matter densities - from the absolute strength of the first peak.

Definition of baryon in:

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Pronunciation: ˈhɒmənɪm
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