Group B


Definition of Group B

: any of various strains of a streptococcus (Streptococcus agalactiae) that include the causative agents of certain infections (such as pneumonia and meningitis) especially of newborn infants usually used attributivelyGroup B streptococcal infections

First Known Use of Group B

1965, in the meaning defined above

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The first known use of Group B was in 1965

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Cite this Entry

“Group B.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2020.

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Group B

\ -ˈbē How to pronounce Group B (audio) \

Medical Definition of Group B

: the Lancefield group of usually beta-hemolytic streptococci that comprises all strains of a species of the genus Streptococcus (S. agalactiae) and that includes the causative agents of certain infections (as septicemia, pneumonia, and meningitis) especially of newborn infants usually used attributivelyaffected with Group B strep — compare group a

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