enantiomer
noun
en·an·tio·mer
i-ˈnan-tē-ə-mər 
: either of a pair of chemical compounds whose molecular structures have a nonsuperimposable mirror-image relationship to each other compare diastereomer
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
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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
Cite this Entry
“Enantiomer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/enantiomer. Accessed 29 May. 2025.
Copy CitationMedical Definition
enantiomer
noun
en·an·tio·mer
in-ˈant-ē-ə-mər
: either of a pair of chemical compounds whose molecular structures have a mirror-image relationship to each other
called also optical antipode
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