quark

[kwawrk, kwahrk] /kwɔrk, kwɑrk/
noun
1.
Physics. any of the hypothetical 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.
Compare color (def 18), flavor (def 5), quantum chromodynamics, quark model.
Origin
coined in 1963 by U.S. physicist Murray Gell-Mann (born 1929), who associated it with a word in Joyce's Finnegans Wake, read variously as English quark croak and German Quark curd, (slang) rubbish, tripe
Can be confused
quark, quirk.
Examples from the web for quark
  • The proton is a baryon that consists of two up and one down quark, and the neutron is two down and one up.
  • Correlations of chiral condensates and quark number densities with static quark sources.
British Dictionary definitions for quark

quark1

/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
Word Origin
C20: coined by James Joyce in the novel Finnegans Wake, and given special application in physics

quark2

/kwɑːk/
noun
1.
a type of low-fat soft cheese
Word Origin
from German
Word Origin and History for quark
n.

1964, applied by U.S. physicist Murray Gell-Mann (b.1929), who said in correspondence with the editors of the OED in 1978 that he took it from a word in James Joyce's "Finnegans Wake" (1939), but also that the sound of the word was in his head before he encountered the printed form in Joyce. German Quark "curds, rubbish" has been proposed as the ultimate inspiration [Barnhart; Gell-Mann's parents were immigrants from Austria-Hungary]. George Zweig, Gell-Mann's co-proposer of the theory, is said to have preferred the name ace for them.

quark in Science
quark
  (kwôrk, kwärk)   
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. See Note at elementary particle. See Table at subatomic particle.