streptococcus

American  

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

noun

Bacteriology.

plural

streptococci

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.

---

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

---

streptococcus Scientific  

/ strĕp′tə-kŏk′əs /

plural

streptococci

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.

---

streptococcus Cultural  

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

---

Other Word Forms

• streptococcal adjective
• streptococcic adjective

Etymology

Origin of streptococcus

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

Example Sentences

A school has reopened following a two-day closure last week due to an outbreak of flu and streptococcus infection.

From BBC • Dec. 15, 2025

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

Some U.S. hospitals and European health authorities also report out-of-season increases in scarlet fever and Group A streptococcus infections.

From Washington Post • Dec. 15, 2022

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

Like septicæmia, this condition is due to pyogenic bacteria, the streptococcus pyogenes being the commonest organism found.

From Manual of Surgery Volume First: General Surgery. Sixth Edition. by Thomson, Alexis