academic gown vs academic robe

academic gown and academic robe both are nouns.

Word	Noun	Adjective	Verb	Adverb
academic gown	Yes	No	No	No
academic robe	Yes	No	No	No

As nouns, academic gown and academic robe are synonyms defined as:

Other synonyms of academic gown include judge's robe.

academic gown (noun)	academic robe (noun)
a gown worn by academics or judges	a gown worn by academics or judges