outbreak

noun

out·​break ˈau̇t-ˌbrāk How to pronounce outbreak (audio)
Synonyms of outbreaknext
1
a
: 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
2
: insurrection, revolt

Synonyms of outbreak

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Lancaster County is the epicenter of the state's outbreak, with 401 cases confirmed so far. — ABC News, 8 Oct. 2026 Over the past two years, nine states have experienced outbreaks that regulators have linked to raw dairy. — Annie Waldman, ProPublica, 8 Oct. 2026 While cases have slowed in Ituri province, the epicenter, the outbreak is spreading in emerging hot spots in North Kivu and South Kivu provinces. — Arkansas Online, 7 Oct. 2026 Leaders from the federal government and the Pennsylvania government have clashed over the response, with much of the debate centered around the five deaths that have come during this outbreak. — Deidre McPhillips, CNN Money, 7 Oct. 2026 See All Example Sentences for outbreak

Word History

First Known Use

1562, in the meaning defined at sense 1a

Time Traveler
The first known use of outbreak was in 1562

Rhymes for outbreak

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Browse Nearby Words

outbrawl
outbreak
outbreaker
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Cite this Entry

“Outbreak.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/outbreak. Accessed 14 Oct. 2026.

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Kids Definition

outbreak

noun
out·​break ˈau̇t-ˌbrāk How to pronounce outbreak (audio)
1
: a sudden increase in activity, use, or acceptance
the outbreak of war
2
: something (as an epidemic or revolution) that breaks out
an outbreak of measles

Medical Definition

outbreak

noun
out·​break ˈau̇t-ˌbrāk How to pronounce outbreak (audio)
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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