out·​break | \ ˈau̇t-ˌbrāk \

Definition of outbreak

1a : a sudden or violent increase in activity or currency the outbreak of war
b : a sudden rise in the incidence of a disease an outbreak of measles
c : a sudden increase in numbers of a harmful organism and especially an insect within a particular area an outbreak of locusts

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Examples of outbreak in a Sentence

there was an immediate outbreak of paper shuffling and a pretense of work when the supervisor passed through the room the government quelled the outbreak with ruthless efficiency

Recent Examples on the Web

An outbreak in California linked to travelers to Disneyland sickened 147 people in the U.S. in 2015. Brianna Abbott, WSJ, "Washington State Becomes Latest Hot Spot in Measles Outbreak," 23 Jan. 2019 The bottom line on public health: Travelers and visitors do spark outbreaks in the US from time to time. Julia Belluz, Vox, "7 bad science and health ideas that should die with 2018," 26 Dec. 2018 The Ebola outbreak in the Democratic Republic of the Congo has spread to a city of nearly 1 million residents. Cathleen O'grady, Ars Technica, "Ebola outbreak reaches city of 1 million residents," 14 Dec. 2018 Their analysis showed a close genetic relationship to the bacteria that caused a 2015 outbreak in the Bugando Medical Center in Mwanza, Tanzania, which caused life-threatening infections in newborns. Jill Kiedaisch, Popular Mechanics, "Drug-Resistant Space Bugs Found Aboard the ISS," 28 Nov. 2018 But Pennsylvania is not the only state experiencing deadly K2 outbreaks in its prisons. Talia Kirkland, Fox News, "Synthetic marijuana use among inmates a ‘disaster waiting to happen,’ expert says," 18 Sep. 2018 The infection first gained prominence in the United States during an outbreak in the mid-1990s, and has shown up nearly every year since, the CDC said. Mihir Zaveri, BostonGlobe.com, "Vegetable trays linked to outbreak," 7 July 2018 The law was introduced to raise the country’s immunization coverage after a measles outbreak in Europe that year with more than 14,000 cases. Gaia Pianigiani, New York Times, "Proof of Children’s Vaccinations? Italy Will Now Take Parents’ Word for It," 5 July 2018 An outbreak in March affected more than two dozen individuals in Chester County, Montgomery County and the state of Delaware. Tricia L. Nadolny, Philly.com, "Measles warning issued in Camden, Burlington Counties," 23 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'outbreak.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of outbreak

1562, in the meaning defined at sense 1a

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Statistics for outbreak

Last Updated

3 Feb 2019

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Time Traveler for outbreak

The first known use of outbreak was in 1562

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More Definitions for outbreak



English Language Learners Definition of outbreak

: a sudden start or increase of fighting or disease


out·​break | \ ˈau̇t-ˌbrāk \

Kids Definition of outbreak

: a sudden occurrence or increase of something an outbreak of chicken pox


out·​break | \ ˈau̇t-ˌbrāk \

Medical Definition of outbreak

1 : a sudden rise in the incidence of a disease an outbreak of measles
2 : a sudden increase in numbers of a harmful organism and especially an insect within a particular area an outbreak of locusts

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More from Merriam-Webster on outbreak

Rhyming Dictionary: Words that rhyme with outbreak

Thesaurus: All synonyms and antonyms for outbreak

Spanish Central: Translation of outbreak

Nglish: Translation of outbreak for Spanish Speakers

Britannica English: Translation of outbreak for Arabic Speakers

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