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

• 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

If your usual scented body wash is triggering flare-ups, swap in Dove’s Sensitive Skin Body Wash. —Lily Wohlner, Allure, 17 Aug. 2025

Any delay in treatment could put the patient at risk of a flare-up or lead to the formation of antibodies that make future infusions less effective. —Samuel Ganz, Sun Sentinel, 17 Aug. 2025

Arlen is full of Amazon vans and culture war flare-ups. —Arkansas Online, 14 Aug. 2025

Diet is individualized in IBD, and tracking symptoms could help in knowing if watermelon leads to any problems, especially during a flare-up. —Amber J. Tresca, Verywell Health, 13 Aug. 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