arsenous anhydride vs arsenic trioxide

arsenous anhydride and arsenic trioxide both are nouns.

Word	Noun	Adjective	Verb	Adverb
arsenous anhydride	Yes	No	No	No
arsenic trioxide	Yes	No	No	No

As nouns, arsenous anhydride and arsenic trioxide are synonyms defined as:

arsenous anhydride and arsenic trioxide: a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer

Other synonyms of arsenous anhydride include arsenic, arsenous oxide, ratsbane, white arsenic.

arsenous anhydride (noun)	arsenic trioxide (noun)
a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer	a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer