交叉
Chiasm \Chi"asm\, Chiasma \Chi*as"ma\, n. [NL. chiasma, fr. Gr. ? two lines placed crosswise, fr. ? to mark with a [chi].] (Anat.) A commissure; especially, the optic commissure, or crucial union of the optic nerves. -- {Chi*as"mal}, a..
chiasma n : an intersection or crossing of two tracts in the form of the letter X [syn: {chiasm}, {decussation}] [also: {chiasmata} (pl)]