chiasma opticum vs optic chiasma

chiasma opticum and optic chiasma both are nouns.

Word	Noun	Adjective	Verb	Adverb
chiasma opticum	Yes	No	No	No
optic chiasma	Yes	No	No	No

As nouns, chiasma opticum and optic chiasma are synonyms defined as:

chiasma opticum and optic chiasma: the crossing of the optic nerves from the two eyes at the base of the brain

Other synonyms of chiasma opticum include optic chiasm.

chiasma opticum (noun)	optic chiasma (noun)
the crossing of the optic nerves from the two eyes at the base of the brain	the crossing of the optic nerves from the two eyes at the base of the brain