enantiomer

noun

en·​an·​tio·​mer i-ˈnan-tē-ə-mər How to pronounce enantiomer (audio)
: either of a pair of chemical compounds whose molecular structures have a nonsuperimposable mirror-image relationship to each other compare diastereomer
enantiomeric adjective

Examples of enantiomer in a Sentence

Recent Examples on the Web If the wrong enantiomers slip into pharmaceuticals, the effects can sometimes be toxic or even lethal. Yasemin Saplakoglu, Quanta Magazine, 6 Sep. 2023 Once a crystal seed forms from the enantiomer that is attracted to the surface, the crystal preferentially grows by incorporating more of the same enantiomer. Yasemin Saplakoglu, Quanta Magazine, 6 Sep. 2023 And then there’s the case of esketamine, which is the S-enantiomer of ketamine, a similar (in molecular structure) but more potent agent than ketamine. Joshua Cohen, Forbes, 5 July 2021 Ketamine is a combination of two enantiomers, or mirror image molecules. Megan Thielking, Scientific American, 6 Mar. 2019 Strangely enough, meth's enantiomer is the active ingredient in Vick's Vapor Inhaler. William Herkewitz, Popular Mechanics, 19 Aug. 2013

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'enantiomer.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Greek enantios + English -mer

First Known Use

circa 1929, in the meaning defined above

Time Traveler
The first known use of enantiomer was circa 1929

Dictionary Entries Near enantiomer

Cite this Entry

“Enantiomer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/enantiomer. Accessed 24 Jul. 2024.

Medical Definition

enantiomer

noun
en·​an·​tio·​mer in-ˈant-ē-ə-mər How to pronounce enantiomer (audio)
: either of a pair of chemical compounds whose molecular structures have a mirror-image relationship to each other

called also optical antipode

enantiomeric adjective
enantiomerically adverb

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