bacillus

noun ba·cil·lus \bə-ˈsi-ləs\

: a straight rod-shaped bacterium that requires oxygen for growth; also : a bacterium that causes disease

plural ba·cil·li\-ˌlī also -lē\

Full Definition of BACILLUS

: any of a genus (Bacillus) of rod-shaped gram-positive usually aerobic bacteria producing endospores and including many saprophytes and some parasites (as B. anthracis of anthrax); broadly : a straight rod-shaped bacterium

: bacterium; especially : a disease-producing bacterium

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Origin of BACILLUS

New Latin, from Medieval Latin, small staff, rod, diminutive of Latin baculus staff, alteration of baculum

First Known Use: 1868

Rhymes with BACILLUS

lapillus

Medical Dictionary

bacillus

noun ba·cil·lus \bə-ˈsil-əs\

plural ba·cil·li \-ˌī also -ē\

Medical Definition of BACILLUS

a capitalized : a genus of rod-shaped gram-positive endospore-producing usually aerobic bacteria of the family Bacillaceae that include many saprophytes and some parasites (as B. anthracis of anthrax) b : any bacterium of the genus Bacillus; broadly : a straight rod-shaped bacterium

: bacterium; especially : a disease-producing bacterium