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

• burst
• flare
• flash
• flicker
• flurry
• flutter
• outbreak
• outburst
• spurt

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 flare-ups of violence at a few of these events don’t come from young people gathering. —Daquan Ford, Chicago Tribune, 15 May 2025

Multiple studies support the impact of temperature and humidity on triggering allergic rhinitis flare-ups (inflammation of the nasal passages). —Rachael Zimlich, Verywell Health, 14 May 2025

One bad flare-up caused me to be homeschooled the second semester of my junior year of high school. —Rickey Fayne, People.com, 13 May 2025

This flare-up on Ukraine’s western border is the latest in a long-running crisis in its bilateral relationship with Poland. —Katya Soldak, Forbes.com, 13 May 2025

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