bacillus

play
noun ba·cil·lus \bə-ˈsi-ləs\

Definition of bacillus

plural

bacilli

play \-ˌlī also -lē\
  1. 1 :  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

  2. 2 :  bacterium; especially :  a disease-producing bacterium

Origin and Etymology of bacillus

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


First Known Use: 1868


BACILLUS Defined for English Language Learners

bacillus

play
noun ba·cil·lus \bə-ˈsi-ləs\

Definition of bacillus for English Language Learners

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


Medical Dictionary

bacillus

play
noun ba·cil·lus \bə-ˈsil-əs\

Medical Definition of bacillus

plural

bacilli

\-ˌī also -ē\play
  1. 1a 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

  2. 2:  bacterium; especially :  a disease-producing bacterium



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