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.
The Ebola outbreak that began in DR Congo is becoming a continental crisis after authorities initially underestimated its spread, the head of Africa’s public health agency told Semafor as new cases were reported as far afield as Nigeria. — Ruben Nyanguila, semafor.com, 23 Oct. 2026 Data from the International Air Transport Association shows global jet fuel prices have surged 113% since the outbreak of Middle East conflicts, reaching approximately 193 dollars per barrel. — CNBC, 23 Oct. 2026 While there is public concern about the spread of the illness, there has not yet been a major outbreak. — Devika Rao, TheWeek, 23 Oct. 2026 To date, ​no Ebola cases associated with this outbreak have been reported in the United ​States, the CDC said. — Reuters, NBC news, 23 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 27 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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