Bacillus anthracis, anthrax - a species of Bacillus that causes anthrax in humans and in animals (cattle and swine and sheep and sheep and rabbits and mice and guinea pigs); can be used a bioweapon

Bacillus globigii, Bacillus subtilis, grass bacillus, hay bacillus - a species of Bacillus found in soil and decomposing organic matter; some strains produce antibiotics

Yersinia pestis - a Bacillus bacteria that causes plague; aerosolized bacteria can be used as a bioweapon

eubacteria, eubacterium, true bacteria - a large group of bacteria having rigid cell walls; motile types have flagella

genus Bacillus - type genus of the Bacillaceae; includes many saprophytes important in decay of organic matter and a number of parasites