up quark

Origin of up quark

First recorded in 1975–80
Also called u quark.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

up quark in Science

up quark

[ŭp]
  1. A quark with a charge of +2/3. Its mass is approximately 10 times the electron mass and is the least mass of all quarks. See Table at subatomic particle.
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