a crystalline, water-insoluble antibiotic obtained from tyrothrycin by extraction, used chiefly in treating local infections caused by Gram-positive organisms.
Main Entry: gram·i·ci·din Pronunciation: "gram-&-'sId-&n Function: noun : an antibacterial mixture produced by a soilbacterium of the genus Bacillus (B. brevis) and used topically against gram-positive bacteria in local infections especially of the eye