clos·​trid·​i·​um klä-ˈstri-dē-əm How to pronounce clostridium (audio)
plural clostridia klä-ˈstri-dē-ə How to pronounce clostridium (audio)
: any of a genus (Clostridium) of spore-forming mostly anaerobic soil or intestinal bacteria see botulinum, c. diff, gas gangrene, tetanus
clostridial adjective

Example Sentences

Recent Examples on the Web If not professionally treated, human waste and other body fluids can spread dangerous diseases such as hepatitis A, clostridium difficile, e-coli, rotavirus and norovirus, MDARD added. Kate Gibson, CBS News, 5 Oct. 2022 That count did not include deaths and illnesses from a nasty bug called clostridium difficile, because the germ still is cowed by the drugs used to treat it., 14 Nov. 2019 Streptococcus A is the bacteria that causes most cases of nectrotizing fasciitis, but Shamoon noted that other types of bacteria, including staph, clostridium, E.coli, and pseudomonas, also can lead to the infection. Kristen Jordan Shamus, Detroit Free Press, 4 July 2019 She was also diagnosed with clostridium difficile — also known as C.diff — infection, which causes inflammation in the colon. Jessica Seaman, The Denver Post, 16 June 2019 All three have required intensive care treatment with an anti-toxin that counteracts the effects of a neurotoxin produced by clostridium botulinum, the bacteria that causes wound botulism. Paul Sisson,, 10 Apr. 2018 Specifically, scientists recovered and cultured clostridium difficile, demonstrating that the exact same bug circulating in human outbreaks is also found in mice. Melanie Grayce West, WSJ, 17 Apr. 2018 So and So's, Sunday's event unfolded as a single version of Margot closely resembling the 2014 edition that shut down because of Edwards' health issues related to a diagnosis of C. Diff, or clostridium difficile colitis. David Lindquist, Indianapolis Star, 1 Jan. 2018 This can prevent infections such as clostridium difficile. Paul Sisson,, 3 Feb. 2018 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'clostridium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


New Latin, genus name, from Greek klōstēr spindle, from klōthein to spin

First Known Use

1884, in the meaning defined above

Time Traveler
The first known use of clostridium was in 1884

Dictionary Entries Near clostridium

Cite this Entry

“Clostridium.” Dictionary, Merriam-Webster, Accessed 7 Dec. 2022.

Medical Definition


clos·​trid·​i·​um kläs-ˈtrid-ē-əm How to pronounce clostridium (audio)
capitalized : a genus of saprophytic rod-shaped or spindle-shaped usually gram-positive bacteria (family Clostridiaceae) that are anaerobic or require very little free oxygen and are nearly cosmopolitan in soil, water, sewage, and animal and human intestines, that are very active biochemically comprising numerous fermenters of carbohydrates with vigorous production of acid and gas, many nitrogen-fixers, and others which rapidly putrefy proteins, and that include important pathogens see blackleg, botulism, c. diff, gas gangrene, tetanus bacillus
plural clostridia -ē-ə How to pronounce clostridium (audio)
: any bacterium of the genus Clostridium
: a spindle-shaped or ovoid bacterial cell
especially : one swollen at the center by an endospore
clostridial adjective

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