pyxidium vs pyxis

pyxidium and pyxis both are nouns.

Word	Noun	Adjective	Verb	Adverb
pyxidium	Yes	No	No	No
pyxis	Yes	No	No	No

As nouns, pyxidium and pyxis are synonyms defined as:

pyxidium and pyxis: fruit of such plants as the plantain; a capsule whose upper part falls off when the seeds are released

pyxidium (noun)	pyxis (noun)
fruit of such plants as the plantain; a capsule whose upper part falls off when the seeds are released	a small box used by ancient Greeks to hold medicines
	fruit of such plants as the plantain; a capsule whose upper part falls off when the seeds are released