ENGLISH
REFERENCE

penicillin

n. uncountable
B2 Upper Intermediate US //ˌpɛnəˈsɪɫən// UK //pˈɛnɪsˌɪlɪn// peni·cillin

n. a powerful medicine that doctors use to kill bacteria and treat infections. It was the first antibiotic ever discovered and has saved many lives.

n. a group of antibiotic drugs derived from Penicillium moulds, used to treat various bacterial infections. It functions by inhibiting the synthesis of bacterial cell walls.


SIMPLE

The doctor gave me penicillin for my ear infection.

CONTEXTUAL

Since the patient was allergic to penicillin, the medical team had to find an alternative antibiotic for the surgery.

COMPLEX

The mass production of penicillin during the mid-twentieth century fundamentally altered the landscape of modern medicine, turning previously fatal infections into manageable conditions.

Origin

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

Usage

Uncountable when referring to the drug generally; can be countable when referring to specific types or doses.

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