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

• burst
• flare
• flare-up
• flash
• flicker
• flurry
• flutter
• outburst
• spurt

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 decline in the wholesale price is due to the absence of major bird flu outbreaks so far in March, which has allowed the egg supply to recover. —Brittney Melton, NPR, 19 Mar. 2025

Right now, Kansas has 68 active TB cases, one of the largest US outbreaks in recent history. —Dylan Scott, Vox, 19 Mar. 2025

The current measles outbreak in the United States has claimed more than 300 lives, and at least one death and potentially two. —Omer Awan, Forbes, 19 Mar. 2025

There have been 10 total gastrointestinal illness outbreaks on cruise ships in 2025, most caused by norovirus. —Nathan Diller, USA TODAY, 18 Mar. 2025

Word History

First Known Use

1562, in the meaning defined at sense 1a

Rhymes for outbreak

• awake
• backache
• beefsteak
• betake
• cheesecake
• cupcake
• daybreak
• earthquake
• eastlake
• forsake
• 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