1. A widespread affliction or calamity, especially one seen as divine retribution.
2. A sudden destructive influx or injurious outbreak: a plague of locusts; a plague of accidents.
3. A cause of annoyance; a nuisance: "the plague of social jabbering" (George Santayana).
4. 1. A highly infectious, usually fatal, epidemic disease; a pestilence.
   2. A highly fatal infectious disease that is caused by the bacterium Yersinia (syn. Pasturella ) pestis, is transmitted primarily by the bite of a rat flea, and occurs in bubonic, pneumonic, and septicemic forms.

1. To pester or annoy persistently or incessantly. See synonyms at harass.
2. To afflict with or as if with a disease or calamity: "Runaway inflation further plagued the wage- or salary-earner" (Edwin O. Reischauer).

[Middle English plage, blow, calamity, plague, from Late Latin plāga, from Latin, blow, wound. V., Middle English plaghen, from Middle Dutch, from plaghe, plague, from Late Latin plāga.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.