- the quark having electric charge 2/3 times the elementary charge and strangeness and charm equal to 0.
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
- 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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.