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magic number

noun, Physics.
1.
the atomic number or neutron number of an exceptionally stable nuclide.
Origin
1945-1950
1945-50
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for magic-number

magic number

noun
1.
(physics) any of the numbers 2, 8, 20, 28, 50, 82, and 126. Nuclides with these numbers of nucleons appear to have greater stability than other nuclides
2.
(chem) a number of atoms that is particularly stable in certain types of compound that have clusters of the same type of atom
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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magic-number in Science
magic number
  (māj'ĭk)   
Any of the numbers, 2, 8, 20, 28, 50, 82, or 126, that represent the number of neutrons or protons in strongly bound and exceptionally stable atomic nuclei. The existence of such stable nuclei is explained by assuming a shell structure for nucleons, much like the shell structure of electron orbitals around the nucleus.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Article for magic-number

magic number

in physics, in the shell models of both atomic and nuclear structure, any of a series of numbers that connote stable structure

Learn more about magic number with a free trial on Britannica.com
Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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10
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