from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Any of various characteristically bluish-green fungi of the genus Penicillium that grow as molds on decaying fruits and ripening cheese and are used in the production of penicillin and in making cheese.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. Any of the blue-green fungi, of the genus Penicillium, that are an important source of antibiotics.

from The Century Dictionary and Cyclopedia

  • n. A genus of saprophytic fungi of the class Ascomycetes, the well-known blue-molds, that are abundant on decaying bread and numerous other decaying substances.
  • n. [l. c] In zoology, same as pencil, 7.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. genus of fungi commonly growing as green or blue molds on decaying food; used in making cheese and as a source of penicillin


from The American Heritage® Dictionary of the English Language, 4th Edition

New Latin Pēnicillium, genus name, from Latin pēnicillus, brush; see pencil.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From the genus name.


  • The first thing I learned was that to make penicillin, you have to grow a mold called penicillium.

    Phineas L. MacGuire . . . Gets Slimed!

  • There are tens of thousands of brilliant biological researchers out there, but only Fleming had the wit to cause penicillium notatum to float in the window.

    Two Kinds of Innovation

  • The search engines would not have realized, as did Sir Alexander Fleming, that the penicillium mold forming on some accidentally spilled rye bread crumbs and preventing staphylococcus bacteria from growing in his Petrie dish could herald the discovery of the life-saving antibiotic, penicillin.

    Marshall P. Duke: Pancake People, Rise Up!

  • He also pierces the cheese slightly later – at approximately 5 or 6 weeks rather than 4 or 5 – giving more time for the acidity to drop before the penicillium roqueforti (blue mould) does its work.

    Both a Blessing and a Curse

  • Blue By Ewe is a Roquefort style cheese made using penicillium roqueforti and is hand salted with Murray River salt.

    Archive 2008-03-01

  • I am also allergic to penicillium it is spelled correctly, and other molds.

    Damning Ourselves

  • From an environmental standpoint alone - there were serious indoor mold problems with stachybotrys, aspergillus, penicillium, chaetomium, trichoderma, fusarium, cladosporium and others found in the toxic home.

    Toxic Mold Wall Street Uncovers Conflict

  • The mold found in Roquefort is called penicillium roqueforti which occurs naturally in caves.

    Everything old is new again..

  • FOTHERGILL: If I tested my pillow and it had 34 penicillium, I'd think fine I'll just get a new one.

    CNN Transcript Feb 2, 2006

  • LAX: Penicillin is the drug that is taken from penicillium notatum.

    The Mold in Dr. Florey�s Coat: The Story of the Penicillin Miracle


Log in or sign up to get involved in the conversation. It's quick and easy.