strep·​to·​coc·​cus | \ ˌstrep-tə-ˈkä-kəs How to pronounce streptococcus (audio) \
plural streptococci\ ˌstrep-​tə-​ˈkä-​ˌkī How to pronounce streptococci (audio) , -​(ˌ)kē ; -​ˈkäk-​ˌsī , -​(ˌ)sē \

Definition of streptococcus

: any of a genus (Streptococcus) of spherical or ovoid chiefly nonmotile and parasitic gram-positive bacteria that divide only in one plane, occur in pairs or chains, and include important pathogens of humans and domestic animals broadly : a coccus occurring in chains

Examples of streptococcus in a Sentence

Recent Examples on the Web Philippines health secretary Francisco Duque III said the man also suffered from streptococcus pneumoniae and influenza. NBC News, "First coronavirus death outside China reported in Philippines," 2 Feb. 2020 Treatments include combatting highly contagious illnesses such as MRSA, Norovirus, influenza, and streptococcus. cleveland, "Germ killers of Avon looking to disinfectant your home," 29 Dec. 2019 Nevertheless, the scientists are rigorously screening mothers participating in these trials for microbes such as HIV and group B streptococcus—a common vaginal bacterium that causes respiratory problems in newborns. Sara Reardon, Scientific American, "Trials Test if C-section Babies Benefit From Mom’s Microbes," 17 Aug. 2019 Necrotizing fasciitis, the medical name for the condition that most call flesh-eating bacteria, Nizet noted, is most often caused by streptococcus or staphylococcus bacteria, usually called Strep and Staph. Paul Sisson, San Diego Union-Tribune, "Expert: Flesh-eating bacteria often present in the body before severe infection takes hold," 19 July 2019 Several different types of bacteria can cause the disease, including streptococcus, the bacteria that causes strep throat, and others found in soil, animals and nature. Julie Mazziotta,, "What to Know About Necrotizing Fasciitis — the Flesh-Eating Bacteria Showing Up at Beaches," 27 June 2019 Officials with the Mid Essex National Health Service Department issued a warning this month after 32 cases of invasive Group A streptococcus (IGAS) were reported in the Braintree and Maldon District as well as in Chelmsford City. Fox News, "Outbreak of rare bacterial infection kills 12 in the UK, officials say," 27 June 2019 The results found all types of bacteria, like staphylococcus, streptococcus, bacillus cereus, and E. coli. Danielle Tullo, House Beautiful, "6 Places Germs Are Hiding In Your House," 11 Oct. 2018 Patrice Comey launched a campaign to require doctors and hospitals to test for Group B streptococcus, a bacterial infection that can be treated with penicillin during delivery if detected toward the end of a pregnancy. Susan Page, USA TODAY, "James Comey: Lessons he learned from the tragic loss of his infant son," 16 Apr. 2018

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

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First Known Use of streptococcus

1877, in the meaning defined above

History and Etymology for streptococcus

New Latin

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The first known use of streptococcus was in 1877

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Last Updated

10 Feb 2020

Cite this Entry

“Streptococcus.” Dictionary, Merriam-Webster, Accessed 19 Feb. 2020.

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How to pronounce streptococcus (audio)

English Language Learners Definition of streptococcus

medical : a type of bacteria that causes diseases in people and animals


strep·​to·​coc·​cus | \ -ˈkäk-əs How to pronounce streptococcus (audio) \

Medical Definition of streptococcus

1 capitalized : a genus of spherical or ovoid chiefly nonmotile and parasitic gram-positive bacteria (family Streptococcaceae) that divide only in one plane, occur in pairs or chains, and include important pathogens of humans and domestic animals
2 plural streptococci\ -​ˈkäk-​ˌ(s)ī How to pronounce streptococci (audio) \ : any bacterium of the genus Streptococcus broadly : a coccus occurring in chains

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Britannica English: Translation of streptococcus for Arabic Speakers Encyclopedia article about streptococcus

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