penicillium

American  

[pen-uh-sil-ee-uhm] / ˌpɛn əˈsɪl i əm /

noun

plural

penicilliums, penicillia

1. any fungus of the genus Penicillium, certain species of which are used in cheesemaking and as the source of penicillin.

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penicillium British  

/ ˌpɛnɪˈsɪlɪəm /

noun

1. any ascomycetous saprotrophic fungus of the genus Penicillium, which commonly grow as a green or blue mould on stale food: some species are used in cheese-making and others as a source of penicillin

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penicillium Scientific  

/ pĕn′ĭ-sĭl′ē-əm /

plural

penicilliums

1. Any of various bluish-green fungi of the genus Penicillium, that grow as molds on decaying fruits, ripening cheeses, and bread, and are used to produce penicillin and certain other antibiotics.

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Etymology

Origin of penicillium

1925–30; < New Latin, equivalent to Latin pēnicill ( us ) brush ( pencil ) + -ium -ium

Example Sentences

Testing revealed the most common species was penicillium chrysogenum, famous because it is used to produce the penicillin antibiotic but it can cause allergic reactions or infections in people with compromised immune systems.

From BBC • Mar. 19, 2026

He eventually found what he was looking for: a strain of penicillium, or blue mold, that, in chickens, reduced levels of an enzyme that cells need to make LDL cholesterol.

From New York Times • Jun. 12, 2024

Although underappreciated at first, Fleming’s discovery proved monumental in the field of immunology—and primed the scientist to recognize the potential of the penicillium mold that dropped into his lab dish in 1928.

From Scientific American • Apr. 27, 2021

But the partnership also found new strains of the penicillium mold, and new methods of culturing it that vastly increased the yield of penicillin.

From Slate • Jul. 20, 2020

Primitive methods are still used in the making and sometimes the ripening is done by penicillium introduced in moldy bread.

From The Complete Book of Cheese by Brown, Robert Carlton