racemicadj.

Brit.

/rəˈsiːmɪk/,

/raˈsiːmɪk/, U.S.

/reɪˈsimɪk/,

/rəˈsimɪk/

Origin: A borrowing from Latin, combined with an English element; modelled on a French lexical item. Etymons: Latin racēmus , -ic suffix.

Etymology: < classical Latin racēmus raceme n. + -ic suffix, after French racémique (in acide racémique (printed acide racénique): J. L. Gay-Lussac Cours de chimie (1828) xxiv. 23).

Chemistry.

a. racemic acid n. a compound (originally obtained from the tartar in grape juice) consisting of equal proportions of the laevo- and dextrorotatory isomers of tartaric acid. Now chiefly historical.

ΘΚΠ

the world > matter > chemistry > organic chemistry > organic acids > [noun] > carboxylic acids > tartar acids

tartaric acid1789

tartarous acid1789

tartareous acidc1790

racemic acid1835

tartrovinic acid1837

tartrelic acid1838

tartromethylic acid1838

tartralic acid1857

tartramic acid1857

tartrethylic acid1857

spirit of tartar1860

tartronic acid1866

1835 Rec. Gen. Sci. 2 97 The term racemic acid given by the French is preferable.

1876 tr. P. Schützenberger On Fermentation 7 It might be thought that..it resulted, like racemic acid, from the union of two active but opposed molecules.

1906 H. J. H. Fenton Notes Qualitative Anal. (new ed.) 121 Racemic acid is distinguished from ordinary tartaric acid by its higher melting point (about 206°c), its optical inactivity and the insolubility of its calcium salt in acetic acid or in ammonium chloride.

1955 B. C. L. Kemp Elem. Org. Chem. (new ed.) xiv. 201 One of the inactive tartaric acids (racemic acid) will be an equimolecular compound of the dextro- and lævo-forms, but what about the second inactive acid?

1997 R. Porter Greatest Benefit to Mankind xiv. 431 It was known that tartaric acid (a waste product of wine-making) and racemic acid had identical chemical compositions but different physical properties.

†b. racemic ether n. an ester of racemic acid; a derivative of racemic acid in which a hydrogen atom is replaced by an alkyl group. Obsolete.

ΚΠ

1857 tr. G. J. Mulder Chem. of Wine xxiv. 306 Racemic ether and water, C⁸H⁴O¹⁰ + C⁴H⁵O, ²HO..will be found in wines containing racemic acid, although its presence also cannot be proved.

1868–77 H. Watts Dict. Chem. V. 39 Racemic Ethers. The only known compounds of this group are the acid racemates of ethyl and methyl.

2. Composed of laevo- and dextrorotatory isomers of a compound in equal molecular proportions, and therefore optically inactive. Also: relating to or involving such optically inactive mixtures.

ΘΚΠ

the world > matter > chemistry > organic chemistry > acids obtained from plants or trees > [adjective] > miscellaneous others

aloetic acid1810

anemonic acid1838

azohumic1863

ipecacuanhic1865

anilic1868

ulmous1868

alorcinic acid1872

racemic1892

racemized1896

lauroyl1939

the world > matter > chemistry > isomerism > [adjective] > of or relating to stereo-isomerism > of or relating to optical isomerism > racemic

racemic1892

racemoid1896

1892 Jrnl. Chem. Soc. 62 ii. 822 The fact that the racemic modification of gulolactone cannot be obtained by crystallisation from water is of general interest, but not without analogy.

1894 M. M. P. Muir & H. F. Morley Watts' Dict. Chem. I. 672/2 The ‘racemic’ camphor, bromo-camphor, and camphoric acid were also prepared by mixture.

1926 H. G. Rule tr. J. Schmidt Text-bk. Org. Chem. 37 In a few instances it is possible, by allowing a solution of the racemic mixture to crystallise under certain conditions, to obtain the two enantiomorphs depositing individually.

1978 G. C. Hill & J. S. Holman Chem. in Context xxiv. 387 Because of the identical properties of the isomers it is very difficult to separate them from a racemic mixture.

1997 Sci. Amer. May 16/2 Many evolutionary theorists believe chirality of one form or another was inevitable, because racemic chemistry would have been too inefficient for carrying out certain biological functions.

This entry has been updated (OED Third Edition, June 2008; most recently modified version published online March 2022).

单词	racemic
释义	racemicadj. Brit. /rəˈsiːmɪk/, /raˈsiːmɪk/, U.S. /reɪˈsimɪk/, /rəˈsimɪk/ Origin: A borrowing from Latin, combined with an English element; modelled on a French lexical item. Etymons: Latin racēmus , -ic suffix. Etymology: < classical Latin racēmus raceme n. + -ic suffix, after French racémique (in acide racémique (printed acide racénique): J. L. Gay-Lussac Cours de chimie (1828) xxiv. 23). Chemistry. 1. a. racemic acid n. a compound (originally obtained from the tartar in grape juice) consisting of equal proportions of the laevo- and dextrorotatory isomers of tartaric acid. Now chiefly historical. ΘΚΠ the world > matter > chemistry > organic chemistry > organic acids > [noun] > carboxylic acids > tartar acids tartaric acid1789 tartarous acid1789 tartareous acidc1790 racemic acid1835 tartrovinic acid1837 tartrelic acid1838 tartromethylic acid1838 tartralic acid1857 tartramic acid1857 tartrethylic acid1857 spirit of tartar1860 tartronic acid1866 1835 Rec. Gen. Sci. 2 97 The term racemic acid given by the French is preferable. 1876 tr. P. Schützenberger On Fermentation 7 It might be thought that..it resulted, like racemic acid, from the union of two active but opposed molecules. 1906 H. J. H. Fenton Notes Qualitative Anal. (new ed.) 121 Racemic acid is distinguished from ordinary tartaric acid by its higher melting point (about 206°c), its optical inactivity and the insolubility of its calcium salt in acetic acid or in ammonium chloride. 1955 B. C. L. Kemp Elem. Org. Chem. (new ed.) xiv. 201 One of the inactive tartaric acids (racemic acid) will be an equimolecular compound of the dextro- and lævo-forms, but what about the second inactive acid? 1997 R. Porter Greatest Benefit to Mankind xiv. 431 It was known that tartaric acid (a waste product of wine-making) and racemic acid had identical chemical compositions but different physical properties. †b. racemic ether n. an ester of racemic acid; a derivative of racemic acid in which a hydrogen atom is replaced by an alkyl group. Obsolete. ΚΠ 1857 tr. G. J. Mulder Chem. of Wine xxiv. 306 Racemic ether and water, C⁸H⁴O¹⁰ + C⁴H⁵O, ²HO..will be found in wines containing racemic acid, although its presence also cannot be proved. 1868–77 H. Watts Dict. Chem. V. 39 Racemic Ethers. The only known compounds of this group are the acid racemates of ethyl and methyl. 2. Composed of laevo- and dextrorotatory isomers of a compound in equal molecular proportions, and therefore optically inactive. Also: relating to or involving such optically inactive mixtures. ΘΚΠ the world > matter > chemistry > organic chemistry > acids obtained from plants or trees > [adjective] > miscellaneous others aloetic acid1810 anemonic acid1838 azohumic1863 ipecacuanhic1865 anilic1868 ulmous1868 alorcinic acid1872 racemic1892 racemized1896 lauroyl1939 the world > matter > chemistry > isomerism > [adjective] > of or relating to stereo-isomerism > of or relating to optical isomerism > racemic racemic1892 racemoid1896 1892 Jrnl. Chem. Soc. 62 ii. 822 The fact that the racemic modification of gulolactone cannot be obtained by crystallisation from water is of general interest, but not without analogy. 1894 M. M. P. Muir & H. F. Morley Watts' Dict. Chem. I. 672/2 The ‘racemic’ camphor, bromo-camphor, and camphoric acid were also prepared by mixture. 1926 H. G. Rule tr. J. Schmidt Text-bk. Org. Chem. 37 In a few instances it is possible, by allowing a solution of the racemic mixture to crystallise under certain conditions, to obtain the two enantiomorphs depositing individually. 1978 G. C. Hill & J. S. Holman Chem. in Context xxiv. 387 Because of the identical properties of the isomers it is very difficult to separate them from a racemic mixture. 1997 Sci. Amer. May 16/2 Many evolutionary theorists believe chirality of one form or another was inevitable, because racemic chemistry would have been too inefficient for carrying out certain biological functions. This entry has been updated (OED Third Edition, June 2008; most recently modified version published online March 2022). < adj.1835
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