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

The virus has now spread further across Africa than any previous Ebola outbreak, with cases in the continent’s central, eastern, and western regions. — Ruben Nyanguila, semafor.com, 30 Oct. 2026

In 1998, during an intense El Niño event, NPR's member station, WUSF, reported that Central Florida experienced one of the deadliest tornado outbreaks, killing 42 people. — Ava Berger, NPR, 29 Oct. 2026

One reason is that past outbreaks were almost all caused by the Ebola virus. — ABC News, 29 Oct. 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