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definitions

optic chiasma

or optic chiasm

noun

a site at the base of the forebrain where the inner half of the fibers of the left and right optic nerves cross to the opposite side of the brain.

Origin of optic chiasma

First recorded in 1870–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Medicine definitions for optic chiasm

optic chiasm

n.

A flattened quadrangular body that is the point of crossing of the fibers of the optic nerves.optic decussation
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.