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

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 Coley dug deeper and found a few other cases of remission from cancer after a streptococcus infection. Greg Kahn, Smithsonian, "Could Immunotherapy Lead the Way to Fighting Cancer?," 22 Mar. 2018 Studies have shown that solutions of cinnamon oil can kill a number of common bacteria, such as streptococcus and E. coli. Sandee Lamotte, CNN, "Cinnamon: Pantry staple -- and medical powerhouse?," 8 Mar. 2018 Just like the successful immunizations against the bacteria that cause measles, mumps and tetanus, a shot to prevent streptococcus infections could save lives and reduce health care costs. Kate Sheridan, Newsweek, "Strep Vaccine Could Save Lives and Reduce Health Care Costs—So Why Don't We Have One?," 26 Feb. 2018 But in 15 to 30 percent of cases, tonsillitis is caused by bacteria, most often a certain type of streptococcus (a.k.a. Claire Gillespie, SELF, "Gabourey Sidibe Is Getting Her Tonsils Out—Here's What That's Like as an Adult," 18 Jan. 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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Last Updated

14 Jul 2019

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Time Traveler for streptococcus

The first known use of streptococcus was in 1877

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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

More from Merriam-Webster on streptococcus

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

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