strep·​to·​coc·​cus | \ ˌstrep-tə-ˈkä-kəs How to pronounce streptococcus (audio) \
plural streptococci\ ˌstrep-​tə-​ˈkä-​ˌkī How to pronounce streptococcus (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 Hayden was intubated, the suit states, and soon diagnosed with GBS meningitis—also known as Group B strep, which is caused by a bacteria (Group B streptococcus) commonly found in gastrointestinal and genital tracts. Roy S. Johnson |, al, "‘Catastrophic failure’ at St. Vincent’s caused newborn’s ‘massive’ brain damage, lawsuit alleges," 14 Sep. 2020 What causes it: Bacteria, usually group A streptococcus (strep) or Staphylococcus aureus (staph) bacteria. Jessica Grose, New York Times, "Name That Rash," 15 Apr. 2020 As recommended by the Centers for Disease Control and Prevention, the report says, all pregnant women should be screened at 35 to 37 weeks gestation for group B streptococcus. Kristen Rogers, CNN, "What you need to have a safe home birth," 20 Apr. 2020 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

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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Time Traveler for streptococcus

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The first known use of streptococcus was in 1877

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Cite this Entry

“Streptococcus.” Dictionary, Merriam-Webster, Accessed 4 Mar. 2021.

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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 streptococcus (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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