Streptococcus viridans

**Semantic type:** Bacterium

**Definition:** A non-taxonomic grouping of Streptococcal bacteria that are either alpha-hemolytic, producing a green coloration on blood agar plates, or nonhemolytic. Within this heterogeneous group, some species are commensal flora while others are human pathogens.

**Synonyms:** - STREPTOCOCCUS VIRIDANS - VGS - Viridans Group Streptococci - Viridans Streptococcal Species - Viridans Streptococci