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

  • n. A microscopic protein particle similar to a virus but lacking nucleic acid, thought to be the infectious agent responsible for scrapie and certain other degenerative diseases of the nervous system.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A self-propagating misfolded conformer of a protein that is responsible for a number of diseases that affect the brain and other neural tissue.
  • n. A petrel of the genus Pachyptila.

from the GNU version of the Collaborative International Dictionary of English

  • n. any of several types of protein particle lacking nucleic acid, believed to be the cause of certain slow-developing infectious diseases such as scapie in sheep, and Creutzfeldt-Jakob disease and Kuru in humans.

from The Century Dictionary and Cyclopedia

  • n. A genus of Procellariidæ, having the bill expanded and strongly beset along the cutting edges with lamellæ like the teeth of a saw; the saw-billed petrels. P. vittata is a blue-and-white petrel inhabiting southern seas. Also Pachyptila.

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

  • n. (microbiology) an infectious protein particle similar to a virus but lacking nucleic acid; thought to be the agent responsible for scrapie and other degenerative diseases of the nervous system


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

pr(oteinaceous) + i(nfectious) + -on1.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From (a reordering of) the initial letters of proteinaceous infectious particle. Coined in 1982 by Stanley B. Prusiner.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Prion (former genus name), from Ancient Greek πρίων ("saw").


  • You say she disputed the name prion because it did not behave as a protein under radiation.

    Tikvah Alper.

  • The infectious agent is commonly called a prion, the pr-i standing for proteinaceous infectious, though my mother, in fact, always disputed the term because her work showed that the agent was not destroyed by radiation that would inactivate both DNA and protein. reply

    Tikvah Alper.

  • Fri, 01/29/2010 - 05: 34 — Naomie (not verified) the name prion

    Tikvah Alper.

  • On October 1, 2009, Octapharma provided a $4.5 million advance to ProMetic on a long-term prion capture resin supply agreement signed in December 2008, linked to minimum yearly purchase orders for the prion capture resin incorporated into Octapharma's manufacturing process for its solvent/detergent treated plasma product, OctaplasLG®.

    Marketwire - Breaking News Releases

  • What causes progressive neurological diseases like "mad-cow" disease or vCJD? vCJD is caused by an unusual protein called a prion (proteinaceous infectious particle).

    Mad-cow Disease

  • Unlike other animals, Dr. Prusiner said, deer give off the infectious agent, a form of protein called a prion, from lymph tissue in their intestinal linings up to a year before they develop the disease.

    Seven Reasons to Stop Baiting Whitetails Now

  • CJD is a prion, which is totaly different from bacteria and viruses to which our systems can develop immunity.

    Jean's Knitting

  • The disease is based on a protein abnormality, when a protein called a prion attacks the thalamus.

    Dr. Michael J. Breus: Sleep Tips: The Link Between Insomnia and Health

  • So this all feels quite far and distant from the rest of us until Max reveals that the research has also identified that this is all caused by a rogue protein known as a prion and then suddenly you think it's right on the doorstep because so was CJD or Mad Cow Disease a few years ago.

    The Family That Couldn't Sleep - Portobello Books

  • The radio reported not long ago that elk kept in a pen where there had previously been infected not sure that's the right word for a prion, which is not exactly infectious elk DID develop the same disorder.

    Chronic Wasting Disease


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  • At the height of the original mad-cow scare - I suppose it was about 1995 or 1996? - I played this word at scrabble and was, to my great chagrin, successfully challenged. It wasn't in the sodding dictionary, and it rankles to this day.

    June 11, 2008

  • Also the name of a bird (petrel). :-)

    June 11, 2008

  • Well, strictly speaking, prions are the infectious agents involved in the transmission of spongiform encephalopathies. The weird part is they are proteins, which had generally not been considered capable of transmitting infection until recently. Rogue proteins folding badly.

    CJD stands for Creuzfeldt-Jakob disease. kuru and scrapie are similar afflictions, occurring in people who eat other people's brains and sheep, respectively.

    February 21, 2007

  • That's Mad Cow Disease for those who aren't biologists.

    December 28, 2006

  • vCJD, Bovine spongiform encephalopathy... All fun! (read: sarcasm)

    December 26, 2006