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levorotation

[lē′və-rō-tā′shən]

n.

A counterclockwise rotation, especially of the plane of polarized light.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
levorotation in Science

levorotation

[lē′və-rō-tā′shən]

The counterclockwise rotation of the plane of polarization of light (as observed when looking straight into the incoming light) by certain substances, such as crystals, and by certain solutions. Levorotation is caused by a particular arrangement of the atoms in a molecule of the substance. Compare dextrorotation.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.