quark

American  

[kwawrk, kwahrk] / kwɔrk, kwɑrk /

noun

• quarks
  plural

1. Physics. any of the particles with spin 1/2, baryon number 1/3, and electric charge 1/3 or −2/3 that, together with their antiparticles, are believed to constitute all the elementary particles classed as baryons and mesons; they are distinguished by their flavors, designated as up (u), down (d), strange (s), charm (c), bottom or beauty (b), and top or truth (t), and their colors, red, green, and blue.

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quark ¹ British  

/ kwɑːk /

noun

1. physics any of a set of six hypothetical elementary particles together with their antiparticles thought to be fundamental units of all baryons and mesons but unable to exist in isolation. The magnitude of their charge is either two thirds or one third of that of the electron

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quark ² British  

/ kwɑːk /

noun

1. a type of low-fat soft cheese

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quark Scientific  

/ kwôrk,kwärk /

1. Any of a group of elementary particles supposed to be the fundamental units that combine to make up the subatomic particles known as hadrons (baryons, such as neutrons and protons, and mesons). There are six different flavors (or types) of quark: up quark, down quark, top quark, bottom quark, charm quark, and strange quark. Quarks have fractional electric charges, such as 1/3 the charge of an electron.

2. See Note at elementary particle See Table at subatomic particle

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Other Word Forms

Noun Inflected Forms

• quarks
  plural

Etymology

Origin of quark

Coined in 1963 by U.S. physicist Murray Gell-Mann (1929–2019), who associated it with a word in Joyce's Finnegans Wake, read variously as English quark croak and German Quark curd, (slang) rubbish, tripe

Explanation

A quark is an elementary particle with an electric charge. When quarks combine, they form another type of particle called a "hadron." If you want to learn more, take up particle physics. Quarks are held together by what physicists call "the strong force" or "the strong nuclear force." The most stable of these quark combinations, or hadrons, are protons and neutrons — the basic building blocks of atoms. In the 1960s, a physicist named Murray Gell-Mann named these particles from a favorite made-up word in James Joyce's book Finnegan's Wake: quark. Gell-Mann's partner reportedly preferred the word ace.

Example Sentences

See Examples For:

quark quarks

The quark model was eventually expanded to include six flavors.

From Science Daily ● Sep. 2, 2026

"In the naïve quark model, there are three quarks inside a proton, but nothing else," said Tommy Tsang, formerly a postdoc at Kent State University, now at DOE's Argonne National Laboratory.

From Science Daily ● Aug. 16, 2026

One promising approach involves mesons, which are particles made of a quark and an anti-quark, bound together with an atomic nucleus.

From Science Daily ● Apr. 25, 2026

While a proton contains two up quarks and one down quark, the Ξcc⁺ replaces the up quarks with heavier charm quarks.

From Science Daily ● Mar. 19, 2026

The fact that confinement prevents one from observing an isolated quark or gluon might seem to make the whole notion of quarks and gluons as particles somewhat metaphysical.

From "A Brief History of Time: And Other Essays" by Stephen Hawking

Gluons are particles that help bind quarks together through the strong force.

From Science Daily ● Sep. 12, 2026

Up, down and strange are also the three lightest types of quarks.

From Science Daily ● Sep. 2, 2026

One possibility is that it represents a hybrid state involving two strange quarks and excited gluons, the particles that carry the strong force.

From Science Daily ● Sep. 2, 2026

"Our findings strongly support the idea that baryon number is more favorably carried and transported by gluons, the particles that hold quarks together, when arranged in this special configuration."

From Science Daily ● Aug. 16, 2026

The origin of the name is an enigmatic quotation from James Joyce: “Three quarks for Muster Mark!”

From "A Brief History of Time: And Other Essays" by Stephen Hawking