pen·​i·​cil·​li·​um | \ ˌpe-nə-ˈsi-lē-əm How to pronounce penicillium (audio) \
plural penicillia\ ˌpe-​nə-​ˈsi-​lē-​ə How to pronounce penicillia (audio) \

Definition of penicillium

: any of a genus (Penicillium) of fungi (such as a blue mold) that are found chiefly on moist nonliving organic matter (such as decaying fruit) and have been grouped with the imperfect fungi but are now often placed with the ascomycetes

Examples of penicillium in a Sentence

Recent Examples on the Web Blue cheese, which has been ripened with cultures of the mold penicillium, includes varieties such as Stilton and Gorgonzola. Jenna Birch, Washington Post, "From feta to American slices, a ranking of cheeses by healthfulness," 2 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'penicillium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of penicillium

1867, in the meaning defined above

History and Etymology for penicillium

New Latin, from Latin penicillus

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The first known use of penicillium was in 1867

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Cite this Entry

“Penicillium.” Dictionary, Merriam-Webster, Accessed 11 Jul. 2020.

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pen·​i·​cil·​li·​um | \ ˌpen-ə-ˈsil-ē-əm How to pronounce penicillium (audio) \

Medical Definition of penicillium

1 capitalized : a genus of fungi (as the blue molds) that have been grouped with the imperfect fungi but are now often placed with the ascomycetes and that are found chiefly on moist nonliving organic matter (as decaying fruit), are characterized by the erect branching conidiophores ending in tufts of club-shaped cells from which conidia are formed in chains, and include molds useful in economic fermentation and the production of antibiotics
2 plural penicillia\ -​ē-​ə How to pronounce penicillia (audio) \ : any mold of the genus Penicillium

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Rhyming Dictionary: Words that rhyme with penicillium Encyclopedia article about penicillium

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