penicillin

/ˌpɛn.ɪˈsɪl.ɪn/

pɛn · ꞮSꞮL · ɪn (3 syllables)

English Noun Top 16,741

Definition

Any of a group of narrow-spectrum antibiotics obtained from Penicillium molds or synthesized, that have a beta-lactam structure and are active against gram-positive bacteria and used in the treatment of various infections and diseases.

Etymology

From translingual Penicillium + -in. Coined by Alexander Fleming after Penicillium notatum (now Penicillium chrysogenum), a fungus from which penicillin is obtained.