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isomer

[ahy-suh-mer] /ˈaɪ sə mər/
noun
1.
Chemistry. a compound displaying isomerism with one or more other compounds.
2.
Also called nuclear isomer. Physics. a nuclide that exhibits isomerism with one or more other nuclides.
Origin
1865-1870
1865-70; back formation from isomeric
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples for isomers
  • Compounds with the same composition but different arrangements are called isomers.
  • One possible source being explored is nuclear isomers.
  • These are frequently termed geometric isomers, in contrast to the previous that are typically termed structural isomers.
  • Cis isomers and trans isomers often have different physical properties.
British Dictionary definitions for isomers

isomer

/ˈaɪsəmə/
noun
1.
(chem) a compound that exhibits isomerism with one or more other compounds
2.
(physics) a nuclide that exhibits isomerism with one or more other nuclides
Derived Forms
isomeric (ˌaɪsəˈmɛrɪk) adjective
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 isomers

isomer

n.

1866, back-formation from isomeric; cf. Greek isomeres "sharing equality," from iso- (see iso-) + meros "part, share" (see merit (n.)).

Online Etymology Dictionary, © 2010 Douglas Harper
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isomers in Medicine

isomer i·so·mer (ī'sə-mər)
n.

  1. Any of two or more substances that are composed of the same elements in the same proportions but differ in properties because of differences in the arrangement of atoms.

  2. Any of two or more nuclei with the same mass number and atomic number that have different radioactive properties and can exist in any of several energy states for a measurable period of time.


i'so·mer'ic (-měr'ĭk) adj.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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isomers in Science
isomer
  (ī'sə-mər)   
Any of two or more compounds, such as lactose and sucrose, composed of the same elements in the same proportions but differing in structure and other properties. There are two types of isomers, structural isomers and stereoisomers.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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isomers in Culture
isomers [(eye-suh-muhrz)]

In chemistry, molecules that contain exactly the same numbers of the same kinds of atoms, but in which the atoms have different structural arrangements.

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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