plague
n. C / Un. a serious disease that spreads quickly and kills many people. It is also used to describe a large number of harmful things, like insects, that arrive at once.
n. a contagious bacterial disease characterized by fever and delirium; more broadly, any widespread affliction or calamity. Often used metaphorically to describe an influx of destructive or unwanted entities.
The city suffered from a terrible plague in the middle ages.
Farmers are worried that a plague of locusts will destroy their entire harvest this season.
Historians continue to debate how the bubonic plague reshaped the economic landscape of Europe by drastically reducing the available labor force.
From Middle English plage, borrowed from Old French plage, from Latin plāga (“blow, wound”), from plangō (“to strike”). Cognate with Middle Dutch plāghe (> Dutch plaag), plāghen (> Dutch plagen); Middle Low German plāge; Middle High German plāge, pflāge (> German Plage); plāgen (> German plagen); Swedish plåga; French plaie, Occitan plaga. Doublet of plaga. Displaced native Old English wōl.
Often used with the preposition 'of' when describing a swarm or a large quantity of something harmful.