|antibiotic (ān'tĭ-bī-ŏt'ĭk) Pronunciation Key
Noun A substance, such as penicillin, that is capable of destroying or weakening certain microorganisms, especially bacteria or fungi, that cause infections or infectious diseases. Antibiotics are usually produced by or synthesized from other microorganisms, such as molds. They inhibit pathogens by interfering with essential intracellular processes, including the synthesis of bacterial proteins. Antibiotics do not kill viruses and are not effective in treating viral infections.