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

: insurrection, revolt

Synonyms of outbreak

• flurry
• burst
• outburst

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

At this time, there aren’t any local outbreaks in California, and current cases of cyclosporiasis infection are not linked to the multi-state outbreak, according to the California Department of Public Health. — Karen Garcia, Los Angeles Times, 10 July 2026

The Congolese authorities declared a fresh Ebola outbreak on May 15, after the disease had been transmitted for weeks without official detection, according to the World Health Organization. — ABC News, 9 July 2026

The outbreak in Michigan began with two cases reported on June 22 and rose steeply at the start of July. — Beth Mole, ArsTechnica, 9 July 2026

In a statement issued on July 4, Michigan officials said that no specific provider of fresh produce had been linked to the outbreak. — Adam Kovac, Scientific American, 9 July 2026

Word History

First Known Use

1562, in the meaning defined at sense 1a

Rhymes for outbreak

• awake
• backache
• beefsteak
• betake
• cheesecake
• cupcake
• daybreak
• earthquake
• forsake
• gouache
• handshake
• headache

Kids 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