gramicidin

noun

gram·​i·​ci·​din ˌgra-mə-ˈsī-dᵊn 

: any of several toxic crystalline polypeptide antibiotics produced by a soil bacterium (Bacillus brevis) and used against gram-positive bacteria in local infections

Word History

Etymology

gram-positive + -i- + -cide + -in entry 1

First Known Use

1940, in the meaning defined above

Medical Definition

gramicidin

noun

gram·​i·​ci·​din ˌgram-ə-ˈsīd-ᵊn 

: an antibacterial mixture produced by a soil bacterium of the genus Bacillus (B. brevis) and used topically against gram-positive bacteria in local infections especially of the eye