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
pr(oteinaceous) + i(nfectious) + -on1.(American Heritage® Dictionary of the English Language, Fourth Edition)
From (a reordering of) the initial letters of proteinaceous infectious particle. Coined in 1982 by Stanley B. Prusiner. (Wiktionary)
From Prion (former genus name), from Ancient Greek πρίων ("saw"). (Wiktionary)