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Synonyms

bacillus

American  
[buh-sil-uhs] / bəˈsɪl əs /

noun

plural

bacilli

  1. any rod-shaped or cylindrical bacterium of the genus Bacillus, comprising spore-producing bacteria.

  2. (formerly) any bacterium.

bacillus British  
/ bəˈsɪləs /

noun

  1. any rod-shaped bacterium, such as a clostridium bacterium Compare coccus spirillum

  2. any of various rodlike spore-producing bacteria constituting the family Bacillaceae , esp of the genus Bacillus

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
bacillus Scientific  
/ bə-sĭl′əs /

plural

bacilli

  1. Any of various pathogenic bacteria, especially one that is rod-shaped.

Etymology

Origin of bacillus

1880–85; < Late Latin, variant of Latin bacillum (diminutive of baculum ) staff, walking stick

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But tuberculosis is also curable and preventable, caused by a bacillus, Mycobacterium tuberculosis, and spread when people who are sick expel bacteria into the air, usually by coughing.

From Washington Post • Oct. 17, 2021

Caused by the bacillus Mycobacterium leprae, it has affected multitudes over thousands of years — and, as a chronic disease with physical manifestations, has been a source of stigma and ostracism.

From Nature • Mar. 3, 2019

And so – not without a certain delight in my own suffering, of course – I sat on the couch, a sniffling bacillus tucked cosily on either side.

From The Guardian • Dec. 13, 2015

Black rats carried fleas that were infested with a bacillus called Yersinia pestis.

From Textbooks • Jan. 1, 2012

There is also another kind of plague to worry about: the plague bacillus is endemic all over the Earth.

From "Cosmos" by Carl Sagan

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.