- an elementary particle having no charge, mass slightly greater than that of a proton, and spin of ½: a constituent of the nuclei of all atoms except those of hydrogen. Symbol: n
Origin of neutron
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for neutron
Deuterium is an isotope of hydrogen containing a proton and neutron in its nucleus, while normal hydrogen has only a proton.Are Comets the Origin of Earth’s Oceans?
Matthew R. Francis
December 14, 2014
You have the atom, which has the neutron, the electron, the proton.‘Crazy’ Harlem Pastor Hates on Obama and Gays
September 28, 2014
While every neutron star has an intense magnetic field, the ones known as magnetars are exceptional.
For that reason, such objects are called pulsars, and they have provided our best data about neutron stars.
The pulses are from a beam of light produced by the intense magnetic field, which sweeps across Earth as the neutron star rotates.
The same thing goes for a proton or electron or neutron or even a neutrino.By Proxy
Gordon Randall Garrett
These units are the positron, the negatron, and the neutron.Cube Root of Conquest
Roger Phillips Graham
The actual limit is when the star has reached the density of a neutron, and this star hasn't collapsed that far by a long shot.Islands of Space
John W Campbell
The Miran answered with the neutron beam, atomic and gamma bombs—and the crumbler ray.
Heat—quantities of heat were being poured into the little ship, and the neutron guns were doing their best to add to it.
- physics a neutral elementary particle with a rest mass of 1.674 92716 × 10 –27 kilogram and spin 1/2; classified as a baryon. In the nucleus of an atom it is stable, but when free it decays
C20: from neutral, on the model of electron
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
Word Origin and History for neutron
Online Etymology Dictionary, © 2010 Douglas Harper
- An electrically neutral subatomic particle in the baryon family, having a mass 1,839 times that of the electron, stable when bound in an atomic nucleus, and having a mean lifetime of approximately 1.0X103 seconds as a free particle. It and the proton form nearly the entire mass of atomic nuclei.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
- An electrically neutral subatomic particle in the baryon family, having a mass of 1.674 X 10-24 grams (1,838 times that of the electron and slightly greater than that of the proton). Neutrons are part of the nucleus of all atoms, except hydrogen, and have a mean lifetime of approximately 1.0X103 seconds as free particles. They consist of a triplet of quarks, including two down quarks and one up quark, bound together by gluons. In radioactive atoms, excess neutrons are converted to protons by beta decay. Beams of neutrons from nuclear reactors are used to bombard the atoms of various elements to produce fission and other nuclear reactions and to determine the atomic arrangements in molecules. See Table at subatomic particle.
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The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.