halobacterium vs halobacteria

halobacterium and halobacteria both are nouns.

Word	Noun	Adjective	Verb	Adverb
halobacterium	Yes	No	No	No
halobacteria	Yes	No	No	No

As nouns, halobacterium and halobacteria are synonyms defined as:

halobacterium and halobacteria: halophiles in saline environments such as the Dead Sea or salt flats

Other synonyms of halobacterium include halobacter.

halobacterium (noun)	halobacteria (noun)
halophiles in saline environments such as the Dead Sea or salt flats	halophiles in saline environments such as the Dead Sea or salt flats