noun \ˈpä-zə-ˌträn\

physics : a very small particle of matter that has a positive charge of electricity and that travels around the nucleus of an atom

Full Definition of POSITRON

:  a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron —called also antielectron

Origin of POSITRON

positive + -tron (as in electron)
First Known Use: 1933

Rhymes with POSITRON

Abadan, Acheron, Ahriman, aileron, alençon, amazon, Amazon, amnion, and so on, antiphon, Aragon, autobahn, balmacaan, Bantustan, baryon, Basilan, bear down on, beat up on, betatron, biathlon, cabochon, call upon, calutron, carillon, carry-on, carry on, celadon, check up on, chorion, colophon, come upon, Culiacán, cyclotron, decagon, decathlon, demijohn, dine out on, early on, echelon, electron, elevon, enteron, epsilon, ethephon, etymon, fall back on, fermion, follow-on, Genghis Khan, get it on, go back on, going on, goings-on, gonfalon, Grand Teton, graviton, hanger-on, harijan, helicon, heptagon, hereupon, hexagon, hold out on, hopping John, Huascarán, hyperon, Isfahan, isochron, Kublai Khan, Kyrgyzstan, lay eyes on, Lebanon, leprechaun, liaison, Lipizzan, load up on, logion, looker-on, macédoine, marathon, Marathon, marzipan, mastodon, Mazatlán, Miquelon, miss out on, morion, move in on, myrmidon, nonagon, noumenon, nucleon, Oberon, octagon, off and on, omicron, Oregon, organon, ostracon, Pakistan, Palawan, pantheon, paragon, Parmesan, parmigiana, Parthenon, peloton, pentagon, pentathlon, Percheron, Phlegethon, Phocion, pick up on, polygon, Procyon, put-upon, Rajasthan, Ramadan, ride herd on, run low on, run out on, run upon, set eyes on, set foot on, set upon, silicon, sneak up on, Süleyman, tachyon, Taiyuan, talkathon, telamon, telethon, thereupon, tie one on, triathlon, Tucumán, upsilon, virion, walkathon, walk out on, whereupon, woebegone, work upon, Yerevan, Xiangtan, Zahedan


noun \ˈpäz-ə-ˌträn\   (Medical Dictionary)

Medical Definition of POSITRON

: a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron—called also positive electron


noun    (Concise Encyclopedia)

Subatomic particle having the same mass as an electron but with an electric charge of +1 (an electron has a charge of 1). It constitutes the antiparticle (see antimatter) of an electron. The existence of the positron was a consequence of the electron theory of P.A.M. Dirac (1928), and the particle was discovered in cosmic rays by Carl D. Anderson (1905–1991) in 1932. Though they are stable in a vacuum, positrons react quickly with the electrons of ordinary matter, producing gamma rays by the process of annihilation. They are emitted in positive beta decay of proton-rich radioactive nuclei and are formed in pair production.


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