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optic axis

noun Crystallography.
  1. (in a crystal exhibiting double refraction) the direction or directions, uniaxial or biaxial, respectively, along which this phenomenon does not occur.

Origin of optic axis

First recorded in 1655–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for optic axis

optic axis

noun
  1. the direction in a uniaxial crystal or one of the two directions in a biaxial crystal along which a ray of unpolarized light may pass without undergoing double refraction
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
optic axis in Medicine

optic axis

n.
  1. The line connecting the anterior and the posterior poles of the eye.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.