Definition of bacillus
bacilliplay \-ˌlī also -lē\
1 : any of a genus (Bacillus) of rod-shaped gram-positive usually aerobic bacteria producing endospores and including many saprophytes and some parasites (such as B. anthracis of anthrax); broadly : a straight rod-shaped bacterium
2 : bacterium; especially : a disease-producing bacterium
Recent Examples of bacillus from the Web
Monsanto’s cotton seed is spliced with genetic material taken from bacterium called bacillus thuringiensis and commonly referred to as BT.
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Origin and Etymology of bacillus
New Latin, from Medieval Latin, small staff, rod, diminutive of Latin baculus staff, alteration of baculum
First Known Use: 1868See Words from the same year
BACILLUS Defined for English Language Learners
Definition of bacillus for English Language Learners
: a straight rod-shaped bacterium that requires oxygen for growth; also : a bacterium that causes disease
Medical Definition of bacillus
bacilli\-ˌī also -ē\play
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: bacterium; especially : a disease-producing bacterium
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