an antibiotic used in treating local Gram-positive bacterial infections: obtained from the soil bacterium Bacillus brevis
Word origin
C20: from Gram(-positive) + -cid(e) + -in
gramicidin in American English
(ˌgræmɪˈsaɪdən)
US
noun
any of a group of chemically related antibiotic polypeptides produced by a soil bacillus (Bacillus brevis) and used in medicines to treat various bacterial infections, esp. of the skin and eyes