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
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
Grills naturally have hot spots, cooler areas, flare-ups, and uneven heat.
—
Katie Rosenhouse, Southern Living, 22 May 2026
Ultraviolet therapy paired with certain oral medications can reduce skin flare-ups.
—Carrie Madormo, Health, 18 May 2026
Indoor air quality concerns spiked during the COVID-19 pandemic and have stayed top of mind through wildfire seasons and allergy flare-ups — making the best hepa air purifier search one of the most common questions home shoppers ask.
—Ryan Brennan
may 18, Kansas City Star, 18 May 2026
People with rosacea can run into challenges during the summer, too, since anything that raises body temperature is a potential trigger for a flare-up.
—Kara Nesvig, Allure, 14 May 2026
See All Example Sentences for flare-up
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Katie Rosenhouse, Southern Living, 22 May 2026
Ultraviolet therapy paired with certain oral medications can reduce skin flare-ups.
—Carrie Madormo, Health, 18 May 2026
Indoor air quality concerns spiked during the COVID-19 pandemic and have stayed top of mind through wildfire seasons and allergy flare-ups — making the best hepa air purifier search one of the most common questions home shoppers ask.
—Ryan Brennan
may 18, Kansas City Star, 18 May 2026
People with rosacea can run into challenges during the summer, too, since anything that raises body temperature is a potential trigger for a flare-up.
—Kara Nesvig, Allure, 14 May 2026
See All Example Sentences for flare-up
Cite this Entry
“Flare-up.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flare-up. Accessed 29 May. 2026.
Copy CitationMedical Definition
flare-up
noun
: a sudden appearance or worsening of the symptoms of a disease or condition
an asthmatic flare-up
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