cocci vs eubacterium

cocci and eubacterium both are nouns.

Word	Noun	Adjective	Verb	Adverb
cocci	Yes	No	No	No
eubacterium	Yes	No	No	No

As nouns, eubacterium is a hypernym of cocci; that is, eubacterium is a word with a broader meaning than cocci:

cocci: any spherical or nearly spherical bacteria
eubacterium: a large group of bacteria having rigid cell walls; motile types have flagella

Other hypernyms of cocci include eubacteria, true bacteria.

cocci (noun)	eubacterium (noun)
any spherical or nearly spherical bacteria	a large group of bacteria having rigid cell walls; motile types have flagella