1
adjective
which stops the spread of bacteria
2
noun
drug (such as penicillin) which is developed from living substances and which stops the spread of microorganisms; he was given a course of antibiotics; antibiotics have no use against virus diseases
broad-spectrum antibiotic = antibiotic used to control many types of bacteria
COMMENT: penicillin is one of the commonest antibiotics, together with streptomycin, tetracycline, erythromycin and many others. Although antibiotics are widely and successfully used, new forms of bacteria have developed which are resistant to them