flare-up

noun

ˈfler-ˌəp 

1

: a sudden outburst or intensification

a flare-up of hostilities

2

: a sudden bursting (as of a smoldering fire) into flame or light

a danger of flare-ups

3

: a sudden appearance or worsening of the symptoms of a disease or condition

an asthmatic flare-up

Synonyms of flare-up

• flurry
• burst
• outburst
• outbreak
• flare

Examples of flare-up in a Sentence

took medication to prevent a flare-up of her asthma

there's no need for an angry flare-up, as we'll take care of the problem immediately

Recent Examples on the Web

But even after this evacuation, the 911 call log and the new county report show sheriff’s deputies responded to an increasing number of spot fires and flare-ups that continued to creep farther west. —Los Angeles Times, 29 May 2026

Be prepared for flare-ups and sticking. —CBS News, 28 May 2026

Firefighters remained on the scene overnight to prevent flare-ups. —Harry Harris, Mercury News, 28 May 2026

The string of flare-ups completely bucked the momentum of the 2025 third-round pick’s rookie season, as Bryant was establishing himself as a near-irreplaceable piece in Denver’s offense. —Luca Evans, Denver Post, 26 May 2026

Word History

First Known Use

1839, in the meaning defined at sense 1

Rhymes for flare-up

• buttercup
• backup
• blowup
• breakup
• buildup
• checkup
• cleanup
• holdup
• hookup
• lineup
• lockup
• makeup

Kids Definition

flare-up

noun

ˈfla(ə)r-ˌəp, 

ˈfle(ə)r-

: a sudden burst (as of flame or anger)

Medical Definition

flare-up

noun

-ˌəp 

: a sudden appearance or worsening of the symptoms of a disease or condition

an asthmatic flare-up