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Synonyms

outbreak

American  
[out-breyk] / ˈaʊtˌbreɪk /

noun

outbreaks plural
  1. a sudden breaking out or occurrence, especially of something bad or unpleasant; eruption.

    the outbreak of war.

  2. a sudden and active manifestation.

    an outbreak of hives.

  3. a sudden increase in the incidence of a disease or medical condition in a particular place or population: a worldwide polio outbreak in the early 1900s.

    a serious outbreak of malaria in northern Uganda;

    a worldwide polio outbreak in the early 1900s.

  4. an outburst.

    an outbreak of temper.

  5. an insurrection, revolt, or mutiny.

  6. a public disturbance; riot.


outbreak British  
/ ˈaʊtˌbreɪk /

noun

  1. a sudden, violent, or spontaneous occurrence, esp of disease or strife

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of outbreak

First recorded in 1595–1605; out- + break

Explanation

A sudden or abrupt onset of something really bad is an outbreak. You could experience an outbreak of measles or an outbreak of violence; either way, try to protect yourself. When you talk about an outbreak of something, it's almost always something terrible, or at least unwanted. You might hear about an outbreak of war in a distant country, or an outbreak of violence in a big city, or an outbreak of disease among farm animals. Outbreak started as a Middle English verb around 1300, becoming a noun meaning "eruption" about three hundred years later.

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Vocabulary lists containing outbreak

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

More than 100 passengers were sickened in a recent norovirus outbreak on the Ruby Princess cruise ship that departed from California last month and arrived back at port Thursday.

From Los Angeles Times • Jul. 2, 2026

The outbreak, which infected 13 people and killed three, involved the Andes virus, a rare hantavirus strain.

From BBC • Jul. 2, 2026

Swiss inflation edged lower in June, the first decline since higher energy prices prompted prices to accelerate after the outbreak of the war in Iran.

From The Wall Street Journal • Jul. 2, 2026

Even worse, the screwworm outbreak has started to spread to the U.S., with 15 confirmed cases.

From MarketWatch • Jun. 30, 2026

Mr. Jones’s personal vision of the Marburg outbreak reminds me of a flashlight pointed down a dark hole.

From "The Hot Zone" by Richard Preston

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