Also found in: Thesaurus, Medical, Encyclopedia, Wikipedia.
Related to optic chiasma: corpus callosum, optic tract
A structure in the brain formed by the partial intersection or crossing of the optic nerve fibers on the underside of the hypothalamus. Also called optic chiasm.
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.