plague

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A highly infectious, usually fatal, epidemic disease; a pestilence.
• noun A virulent, infectious disease that is caused by the bacterium Yersinia pestis (syn. Pasteurella pestis) and is transmitted primarily by the bite of fleas from an infected rodent, especially a rat. In humans it occurs in bubonic form, marked by lymph node enlargement, and in pneumonic form, marked by infection of the lungs, and can progress to septicemia.
• noun A widespread affliction or calamity seen as divine retribution.
• noun An influx or large number of destructive or unwanted things, especially animals.
• noun Something that causes persistent hardship, trouble, or annoyance.
• transitive verb To pester or annoy persistently or incessantly. synonym: harass.
• transitive verb To cause suffering or hardship for.
• transitive verb To be a widespread or continuous problem or defect in.

from The Century Dictionary.

• noun A blow or calamity; severe trouble or vexation; also, one who or that which troubles or vexes, or ravages or destroys.
• noun Any epidemic disease of high mortality.
• noun As an expletive with the article the, used like the devil, the deuce, etc. Compare devil, 7.
• To vex; harass; trouble; annoy; tease.
• To infest with disease, calamity, or natural evil of any kind.
• Synonyms Torment, Worry, etc. (see tease), gall, bore.
• To afflict.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb To infest or afflict with disease, calamity, or natural evil of any kind.
• transitive verb Fig.: To vex; to tease; to harass.
• noun That which smites, wounds, or troubles; a blow; a calamity; any afflictive evil or torment; a great trail or vexation.
• noun (Med.) An acute malignant contagious fever, that often prevails in Egypt, Syria, and Turkey, and has at times visited the large cities of Europe with frightful mortality; hence, any pestilence.
• noun See Rinderpest.
• noun a spot or mark of the plague; hence, a token of something incurable.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The bubonic plague, the pestilent disease caused by the virulent bacterium Yersinia pestis.
• noun pathology An epidemic or pandemic caused by any pestilence, but specifically by the above disease.
• noun A widespread affliction, calamity or destructive influx, especially when seen as divine retribution.
• noun A grave nuisance, whatever greatly irritates
• verb transitive To harass, pester or annoy someone persistently or incessantly.
• verb transitive To afflict with a disease or other calamity.

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

• verb cause to suffer a blight
• noun any large scale calamity (especially when thought to be sent by God)
• noun an annoyance
• noun any epidemic disease with a high death rate
• noun a swarm of insects that attack plants
• verb annoy continually or chronically
• noun a serious (sometimes fatal) infection of rodents caused by Yersinia pestis and accidentally transmitted to humans by the bite of a flea that has bitten an infected animal