|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|
|[C20: coined by James |
|quark (kwôrk, kwärk) Pronunciation Key
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.
Note: No quarks have been seen in the laboratory because, according to current theory, they cannot exist as free particles.