parallelopipedon vs parallelepiped

parallelopipedon and parallelepiped both are nouns.

Word	Noun	Adjective	Verb	Adverb
parallelopipedon	Yes	No	No	No
parallelepiped	Yes	No	No	No

As nouns, parallelopipedon and parallelepiped are synonyms defined as:

parallelopipedon and parallelepiped: a prism whose bases are parallelograms

Other synonyms of parallelopipedon include parallelepipedon, parallelopiped.

parallelopipedon (noun)	parallelepiped (noun)
a prism whose bases are parallelograms	a prism whose bases are parallelograms