streptococcus

American  

[strep-tuh-kok-uhs] / ˌstrɛp təˈkɒk əs /

noun

Bacteriology.

• streptococci
  plural

1. any of several spherical or oval bacteria of the genus Streptococcus, occurring in pairs or chains, certain species of which are pathogenic for humans, causing scarlet fever, tonsillitis, etc.

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streptococcus British  

/ ˌstrɛptəʊˈkɒkəl, -ˈkɒksɪk, ˌstrɛptəʊˈkɒkəs, ˌstrɛptəʊˈkɒkɪk /

noun

1. Often shortened to: strep.  any Gram-positive spherical bacterium of the genus Streptococcus, typically occurring in chains and including many pathogenic species, such as S. pyogenes, which causes scarlet fever, sore throat, etc: family Lactobacillaceae

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streptococcus Scientific  

/ strĕp′tə-kŏk′əs /

• streptococci
  plural

1. Any of various bacteria of the genus Streptococcus that are gram-positive cocci and are normally found on the skin and mucous membranes and in the digestive tract of mammals. One type of streptococcus, Group A, is a common pathogen in humans and causes various infections, including strep throat, scarlet fever, pneumonia, and some types of impetigo.

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streptococcus Cultural  

1. A category of bacteria that can cause various infections in humans, including scarlet fever and strep throat.

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Other Word Forms

Derived Forms

• streptococcal
  adjective
• streptococcic
  adjective

Inflected Forms

Nouns

• streptococci
  plural

Etymology

Origin of streptococcus

From New Latin, dating back to 1875–80; see origin at strepto-, coccus

Example Sentences

See Examples For:

streptococcus streptococci

And she decides that the bacteria she’s going to target with her vaccine is hemolytic streptococcus, which had been showing up again and again in flu patients.

From Scientific American ● Oct. 19, 2023

Deliveries of antibiotics for the treatment of group A streptococcus infection are being sped up to reach wholesalers and pharmacies across Northern Ireland in the coming days.

From BBC ● Dec. 11, 2022

The UK Sepsis Trust said a streptococcus A infection could lead to sepsis.

From BBC ● Dec. 7, 2022

Health officials in Britain said several children had recently died after being diagnosed with invasive Group A streptococcus, sounding the alarm for schools and prompting parents to spring to action.

From New York Times ● Dec. 6, 2022

If the streptococcus is successfully isolated, inoculate serum bouillon cultivations into the mouse, guinea-pig, and rabbit, to determine its pathogenicity and virulence.

From The Elements of Bacteriological Technique A Laboratory Guide for Medical, Dental, and Technical Students. Second Edition Rewritten and Enlarged. by J. W. H. (John William Henry) Eyre

At the same time, arginine slightly increased the presence of streptococci that are better at metabolizing arginine.

From Science Daily ● Jan. 9, 2026

And it suggests that hemolytic streptococci vaccines provided “significant protection” against pneumonia and mortality.

From Scientific American ● Oct. 19, 2023

The scratch became infected by streptococci and staphylococci and spread to his eyes and scalp, according to “The Mold in Dr. Florey’s Coat.”

From Washington Post ● Jul. 11, 2020

Necrotizing fasciitis, otherwise known as flesh-eating disease, can be caused when a wound is infected with group-A streptococci or by staphylococci, common bacteria that live on people's skin and in their noses.

From Reuters ● Jul. 6, 2012

The toxins of diphtheria bacilli and streptococci are produced when the organisms have been infected by bacteriophage; it is the virus that provides the code for toxin.

From "The Lives of a Cell" by Lewis Thomas