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proton

[proh-ton] /ˈproʊ tɒn/
noun, Physics, Chemistry
1.
a positively charged elementary particle that is a fundamental constituent of all atomic nuclei. It is the lightest and most stable baryon, having a charge equal in magnitude to that of the electron, a spin of ½, and a mass of 1.673 × 10− 27 kg. Symbol: P.
Origin
1915-1920
1915-20; noun use of Greek prôton, neuter of prôtos first
Related forms
protonic, adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for protonic

protonic

/prəʊˈtɒnɪk/
adjective
1.
(chem) (of a solvent, such as water) able to donate hydrogen ions to solute molecules

proton

/ˈprəʊtɒn/
noun
1.
a stable, positively charged elementary particle, found in atomic nuclei in numbers equal to the atomic number of the element. It is a baryon with a charge of 1.602176462 × 10–19 coulomb, a rest mass of 1.672 62159 × 10–27 kilogram, and spin 1/2
Word Origin
C20: from Greek prōtos first
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for protonic
proton
1920, coined by Eng. physicist Ernest Rutherford (1871-1937) from Gk. proton, neut. of protos "first," supposedly because hydrogen was hypothesized as a constituent of all the elements. The word was used earlier in embryology (1893) at a transl. of Ger. anlage ("fundamental thing") based on Aristotle's phrase he prote ousia to proton.
Online Etymology Dictionary, © 2010 Douglas Harper
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protonic in Medicine

proton pro·ton (prō'tŏn')
n.
A stable, positively charged subatomic particle in the baryon family having a mass 1,836 times that of the electron.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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protonic in Science
proton
  (prō'tŏn')   
A stable subatomic particle in the baryon family having a mass of 1.672 × 10-24 grams (1,836 times that of the electron) and a positive electric charge of approximately 1.602 × 10-19 coulombs. Protons make up part of the nucleus of all atoms except hydrogen, whose nucleus consists of a single proton. In neutral atoms, the number of protons is the same as the number of electrons. In positively charged atoms, the number of protons is greater than the number of electrons, and in negatively charged atoms electrons outnumber protons. Protons are believed to be composed of two up quarks and one down quark. See Table at subatomic particle.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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protonic in Culture
proton [(proh-ton)]

An elementary particle with a positive charge, found in the nucleus of an atom.

Note: A proton is over a thousand times heavier than an electron.
Note: Protons and neutrons make up most of an atom's mass.
The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Difficulty index for proton

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Word Value for protonic

12
15
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