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definitions

chiral

[kahy-ruh l]
adjective Chemistry.
  1. (of a molecule) not superimposable on its mirror image.

Origin of chiral

1894; chir- < Greek cheír hand + -al1; coined by Lord Kelvin
Related formschi·ral·i·ty [kahy-ral-i-tee] /kaɪˈræl ɪ ti/, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Word Origin and History for chiral
adj.

1894, a hybrid coined by Lord Kelvin from Latinized comb. form of Greek kheir "hand" (from PIE *ghes- "hand;" see chiro-) + -al (1).

Online Etymology Dictionary, © 2010 Douglas Harper
chiral in Medicine

chiral

[kī′rəl]
adj.
  1. Of or relating to the structural characteristic of a molecule that makes it impossible to superimpose it on its mirror image.
Related formschi•ral′i•ty (kī-răl′ĭ-tē) n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.