bacillus vs true bacteria

bacillus and true bacteria both are nouns.

Word	Noun	Adjective	Verb	Adverb
bacillus	Yes	No	No	No
true bacteria	Yes	No	No	No

As nouns, true bacteria is a hypernym of bacillus; that is, true bacteria is a word with a broader meaning than bacillus:

bacillus: aerobic rod-shaped spore-producing bacterium; often occurring in chainlike formations; found primarily in soil
true bacteria: a large group of bacteria having rigid cell walls; motile types have flagella

Other hypernyms of bacillus include eubacteria, eubacterium.

bacillus (noun)	true bacteria (noun)
aerobic rod-shaped spore-producing bacterium; often occurring in chainlike formations; found primarily in soil	a large group of bacteria having rigid cell walls; motile types have flagella