outbreak
noun
out·break
ˈau̇t-ˌbrāk 
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
Earlier Canary Island outbreaks linked to amoebae followed intense wave activity.
—
Aamir Khollam, Interesting Engineering, 12 Dec. 2025
Gastrointestinal outbreaks are very contagious and can spread easily in a school.
—Stephanie Stahl, CBS News, 12 Dec. 2025
Rare breakthrough cases in partially or fully vaccinated people are more likely to happen during a large outbreak, according to epidemiologists, because so many become exposed as the virus rips through unvaccinated people.
—Arkansas Online, 12 Dec. 2025
The South Carolina Department of Health (DPH) reported in a media briefing on Wednesday that the current number of measles cases has reached 111 as part of the current Spartanburg County outbreak.
—Angelica Stabile, FOXNews.com, 11 Dec. 2025
See All Example Sentences for outbreak
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Aamir Khollam, Interesting Engineering, 12 Dec. 2025
Gastrointestinal outbreaks are very contagious and can spread easily in a school.
—Stephanie Stahl, CBS News, 12 Dec. 2025
Rare breakthrough cases in partially or fully vaccinated people are more likely to happen during a large outbreak, according to epidemiologists, because so many become exposed as the virus rips through unvaccinated people.
—Arkansas Online, 12 Dec. 2025
The South Carolina Department of Health (DPH) reported in a media briefing on Wednesday that the current number of measles cases has reached 111 as part of the current Spartanburg County outbreak.
—Angelica Stabile, FOXNews.com, 11 Dec. 2025
See All Example Sentences for outbreak
Cite this Entry
“Outbreak.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/outbreak. Accessed 14 Dec. 2025.
Copy CitationKids Definition
outbreak
noun
out·break
ˈau̇t-ˌbrāk
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
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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