Group A

noun

: any of various strains of a streptococcus (Streptococcus pyogenes) that include the causative agents of pharyngitis, scarlet fever, septicemia, some skin infections, rheumatic fever, and glomerulonephritis
usually used attributively
Group A strep throat

Word History

First Known Use

1945, in the meaning defined above

Time Traveler
The first known use of Group A was in 1945

Dictionary Entries Near Group A

Cite this Entry

“Group A.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Group%20A. Accessed 18 Jul. 2024.

Medical Definition

Group A

noun
: the Lancefield group of beta-hemolytic streptococci that comprises all strains of a species of the genus Streptococcus (S. pyogenes) and that includes the causative agents of pharyngitis, scarlet fever, septicemia, some skin infections (as pyoderma and erysipelas), rheumatic fever, and glomerulonephritis
usually used attributively
Group A streptococcal infections
compare group b
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