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 (rā-sē′mĭk, -sĕm′ĭk, rə-)
Of or relating to a chemical mixture that contains equal quantities of dextrorotatory and levorotatory forms of a compound and therefore does not rotate the plane of incident polarized light.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(rəˈsiːmɪk; -ˈsɛm-) or


(Chemistry) chem of, concerned with, or being a mixture of equal amounts of enantiomers and consequently having no optical activity
[C19: from raceme (as in racemic acid) + -ic]
racemism n
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(reɪˈsi mɪk, -ˈsɛm ɪk, rə-)

noting or pertaining to any of various organic compounds that are optically inactive but separable into dextrorotatory and levorotatory forms.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The patent includes claims that cover compositions of the immunologically active enantiomer of the cationic lipid R-1,2-dioleoyl-3-trimethyl-ammonium-propane or its racemic mixture with Granulocyte-macrophage colony-stimulating factor to reduce the population of myeloid derived suppressor cells within the tumor microenvironment.
The process developed Takasago International Corporation produces pure menthol (-) enantiomer while the Haarmann-Reimer process produces a racemic mixture of menthol enantiomers that can be separated by chiral resolution.
Clenbuterol is a racemic mixture of two enantiomers banned in sport since 1992.
DeuteRx, LLC has pioneered 'deuterium-enabled chiral switching.' a revolutionary approach to improve racemic.
failed to prove that there was a difference in intraoperative values of arterial pressure between the patients in spinal anesthesia who received levobupivacaine versus those who received racemic bupivacaine.
Furthermore, most formulations of chiral pesticides are composed of racemic mixtures, and it is, therefore, essential to define their stereoselectivity patterns to better estimate risk assessment.
An important milestone for antidepressant drug development was, therefore, achieved in 2016--when an intranasal spray formulation of esketamine, the S(+)-enantiomer of racemic ketamine was granted FDA "breakthrough therapy" designation for the indication of major depressive disorder (MDD) with "imminent risk for suicide." Several years earlier, the drug manufacturer Janssen had initiated studies of esketamine for TRD, which have reported rapid antidepressant effects similar to ketamine.
[6,7,8] But there have been few studies demonstrating a clinically significant benefit to Levobupivacaine over racemic bupivacaine for paediatric regional anaesthesia.
S-AM is equally efficacious at half-dose with better tolerability and lesser incidence of peripheral edema than racemic amlodipine (Amlo) [6].