I. bəˈsiləs noun
Etymology: New Latin, from Medieval Latin bacillus small staff, alteration of Latin baculum — more at bacterium
1. capitalized : a large genus (the type of the family Bacillaceae) of aerobic rod-shaped bacteria producing endospores that do not thicken the rod, often forming long chains and rhizoid colonies, and as now restricted including (1) many saprophytes of soil, water, and comparable habitats that are important in the natural decay of organic matter and (2) a number of parasites (as B. anthracis the cause of anthrax, B. larvae of American foulbrood, and B. popilliae causing milky disease in the Japanese beetle) — compare clostridium
2. plural bacil·li -ˌlī, -ilē
a. : any member of the genus Bacillus ; broadly : any straight rod-shaped bacterium — distinguished from coccus and spirillum
b. : bacterium ; especially : a disease-producing bacterium
Synonyms: see microorganism
II. noun
Usage: capitalized
Etymology: New Latin, from Medieval Latin, small staff
: a genus of long slender wingless Old World stick insects commonly made type of a widely distributed family