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optical activity

noun Physical Chemistry.

the ability of a substance to rotate the plane of polarization of plane-polarized light.

Origin of optical activity

First recorded in 1875–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for optical activity

optical activity

noun

the ability of substances that are optical isomers to rotate the plane of polarization of a transmitted beam of plane-polarized light
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
optical activity in Medicine

optical activity

n.

The property of an asymmetrical molecule in solution to rotate the plane of polarized light either clockwise or counterclockwise.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.