alpha (alpha)-hemolytic streptococci

al·pha (α)-he·mo·lyt·ic strep·to·coc·ci

(al'fă-hē'mō-lit'ik strep-tŏ-kok'sī) Streptococci that form a green zone around the colony on a blood-agar medium due to incomplete hemolysis of erythrocytes.
See also: Streptococcus viridans