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 task of containing Pennsylvania’s measles outbreak would have been herculean in any circumstance. — Amesh Adalja, Washington Post, 11 Sep. 2026

The outbreak in eastern Congo is spreading under extremely difficult conditions, fueled by insecurity, displacement, a health workers' strike and intense population movements. — Jean-Yves Kamale, Arkansas Online, 11 Sep. 2026

The Philippines, which imports 98% of its oil from the Middle East, was hit hard by the outbreak of the Iran war in February. — Angelica Ang, Fortune, 10 Sep. 2026

Meanwhile, the region's healthcare system is already stretched thin, treating children with malnutrition and outbreaks of malaria or measles on a regular basis. — Durrie Bouscaren, NPR, 10 Sep. 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