outbreak

noun

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

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.
Advertisement The rise in flu cases around the continent, as well as outbreaks in Europe earlier this year, have led some medical experts to warn that influenza may be evolving to spread more quickly or earlier than typical in some regions. Miranda Jeyaretnam, Time, 10 Oct. 2025 Experts say that any amount of measles spread is cause for concern, and large outbreaks highlight the dangers of declining vaccination rates. Deidre McPhillips, CNN Money, 10 Oct. 2025 Like many retail businesses, Algin Furniture was forced to change and adapt after the COVID-19 outbreak. Alexander Coolidge, Cincinnati Enquirer, 9 Oct. 2025 This timeline is unusual to Indiana, which typically sees outbreaks in July. Sophie Hartley, IndyStar, 9 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Outbreak.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/outbreak. Accessed 17 Oct. 2025.

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

More from Merriam-Webster on outbreak

Last Updated: - Updated example sentences
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