chi·​ral | \ ˈkī-rəl How to pronounce chiral (audio) \

Definition of chiral

: of or relating to a molecule that is not superimposable on its mirror image

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Other Words from chiral

chirality \ kī-​ˈra-​lə-​tē How to pronounce chirality (audio) , kə-​ \ noun

Examples of chiral in a Sentence

Recent Examples on the Web

As plants die, their chiral molecules die with them. David Grossman, Popular Mechanics, "Alien Plant Hunter Taking First Steps on Earth. Next Stop: Jupiter," 22 Aug. 2019 Or did chemical and physical forces conspire to create chiral molecules before life arose? Quanta Magazine, "Interstellar Find Adds Life to Old Debate," 20 June 2016 But the cross-chiral ribozyme binds based on the molecule’s shape rather than its sequence. Quanta Magazine, "A New Step in Re-Creating First Life on Earth," 25 Aug. 2016 Geniuses of the past reveled in mechanical manifestations of chiral geometry, which are oddly beautiful as well as being useful. Frank Wilczek, WSJ, "The Peculiar Power of Nature’s Left and Right," 5 July 2018 The other route is the chiral vortical symmetry, which requires that the plasma be rotating. John Timmer, Ars Technica, "Taking quark-gluon plasma for a spin may un-break a fundamental symmetry," 2 Aug. 2017 Today, pharmaceutical companies work harder to separate the active and inactive forms of molecules, and the Food and Drug Administration issued rules to crack down on many chiral drugs in the 1990s. Joanna Klein, New York Times, "How Pasteur’s Artistic Insight Changed Chemistry," 14 June 2017 A primary inspiration was found in chemistry and chiral molecules, identically mirrored structures with different purposes. Doug Bierend, WIRED, "This Movie Works Whether You Play It Backward or Forward," 12 Feb. 2014 The drug also contained a chiral molecule that caused disastrous side effects in many babies. Joanna Klein, New York Times, "How Pasteur’s Artistic Insight Changed Chemistry," 14 June 2017

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

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First Known Use of chiral

1894, in the meaning defined above

History and Etymology for chiral

chir- + -al entry 1

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Learn More about chiral

Dictionary Entries near chiral





chiral center



Statistics for chiral

Last Updated

3 Sep 2019

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Time Traveler for chiral

The first known use of chiral was in 1894

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More Definitions for chiral


chi·​ral | \ ˈkī-rəl How to pronounce chiral (audio) \

Medical Definition of chiral

1a of a molecule : having a structure that is nonsuperimposable on its mirror image chiral molecules
b : relating to or composed of chiral molecules In discussions of chiral drugs, thalidomide is sometimes cited as a prime example of a drug that differs strikingly in the properties of its two enantiomers.— Stephen C. Stinson, Chemical & Engineering News, 19 Sept. 1994
2 : of, relating to, or being a chiral center

Other Words from chiral

chirality \ kī-​ˈral-​ət-​ē How to pronounce chirality (audio) \ noun, plural chiralities

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