isomer

noun iso·mer \ ˈī-sə-mər \

1 : one of two or more compounds, radicals, or ions that contain the same number of atoms of the same elements but differ in structural arrangement and properties

2 : a nuclide isomeric with one or more others

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Recent Examples of isomer from the Web

The problem is that many physicists doubt the feasibility of an isomer bomb.

— david hambling, Popular Mechanics, "9 Ways the U.S. Could Bomb North Korea's Deepest Bunkers," 12 Sep. 2017
L-alanine and D-alanine are BEST classified as what type of isomers?

— brian whitehead, Orange County Register, "Troy High’s Science Bowl team practicing for redemption at national finals," 14 Feb. 2017
But the military research into isomers still continues.

— david hambling, WIRED, "Darpa’s Handheld Nuclear Fusion Reactor," 6 July 2009

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'isomer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of isomer

International Scientific Vocabulary, back-formation from isomeric

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First Known Use: 1855

in the meaning defined at sense 1

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isomer

noun iso·mer \ ˈī-sə-mər \

1 : any of two or more compounds, radicals, or ions that contain the same number of atoms of the same elements but differ in structural arrangement and properties

2 : a nuclide isomeric with one or more others

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