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

The sun’s intense flare-ups had put the telescope on a downward spiral faster than engineers anticipated. — Marcia Dunn, Los Angeles Times, 27 Sep. 2026

The sun's intense flare-ups had put the telescope on a downward spiral faster than engineers anticipated. — Arkansas Online, 26 Sep. 2026

Since the staging area for firefighters, utility workers, national guard, and police was next to our house, for the next few days firefighters were able to put out flare-ups in and around our backyard. — The Christian Science Monitor, Christian Science Monitor, 25 Sep. 2026

The four officials spoke on condition of anonymity as they were not authorized to talk to the media about the latest flare-up. — ABC News, 23 Sep. 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