up quark

noun Physics.

the quark having electric charge 2/3 times the elementary charge and strangeness and charm equal to 0.
Also called u quark.

Origin of up quark

First recorded in 1975–80

Words nearby up quark

up in arms, up in the air, up on something, be, up one's alley, up one's sleeve, up quark, up the creek, up the river, up the wall, up to, up to a point

Scientific definitions for up quark

up quark
[ ŭp ]

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.