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definitions

vergence

[vur-juh ns]
noun Ophthalmology.
  1. the turning motion of the eyeballs toward or away from each other.Compare convergence(def 4), divergence(def 3).

Origin of vergence

First recorded in 1900–05; verge2 + -ence
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for vergence

vergence

noun
  1. the inward or outward turning movement of the eyes in convergence or divergence

Word Origin for vergence

C19: from verge ² + -ence
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
Word Origin and History for vergence
n.

1902, from verge + -ence.

Online Etymology Dictionary, © 2010 Douglas Harper
vergence in Medicine

vergence

[vûr′jəns]
n.
  1. A disjunctive movement of the eyes in which the fixation axes are not parallel.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.