Noun | 1. | neomycin - an antibiotic obtained from an actinomycete and used (as a sulphate under the trade name Neobiotic) as an intestinal antiseptic in surgery antibiotic, antibiotic drug - a chemical substance derivable from a mold or bacterium that can kill microorganisms and cure bacterial infections; "when antibiotics were first discovered they were called wonder drugs" antiseptic - a substance that destroys micro-organisms that carry disease without harming body tissues |