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.
Firefighters struggled to contain the initial outbreak, and strong winds, allied to the withered land, saw the flames quickly spread. — Chris Marshall-Bell, New York Times, 3 Sep. 2026 The pediatric outbreaks that get flagged don't reflect the true gravity of the HIV crisis, public health experts warn. — Betsy Joles, NPR, 2 Sep. 2026 Ebola is caused by a collection of viruses called orthoebolaviruses — with the Bundibugyo virus having been identified in the current outbreak. — Cara Lynn Shultz, PEOPLE, 2 Sep. 2026 The Africa Centers for Disease Control and Prevention said that the outbreak is possibly three times larger than the number of cases recorded, as surveillance and contact tracing are still weak. — Constant Same Bagalwa, Los Angeles Times, 2 Sep. 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 4 Sep. 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
Last Updated: - Updated example sentences
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