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
This filtration system ensures that your floors are getting their most thorough clean, while also ridding your space of irritants like dust that can cause allergy flare-ups.
—
Yelena Moroz Alpert, Architectural Digest, 3 Sep. 2025
Near the Teakettle Experimental Forest, heavier fuels in flatter terrain will continue to smolder with occasional flare-ups.
—Ca Wildfire Bot, Sacbee.com, 2 Sep. 2025
The shoot was impacted nonetheless by a flare-up in tensions between Iran and Israel – after the latter killed a number of top military officials in an airstrike on the Iranian consulate in Damascus in April 2024.
—Melanie Goodfellow, Deadline, 2 Sep. 2025
Pearce has been living with the heart condition for nearly five years and has been experiencing flare-ups since 2020.
—Lauryn Overhultz, FOXNews.com, 30 Aug. 2025
See All Example Sentences for flare-up
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Yelena Moroz Alpert, Architectural Digest, 3 Sep. 2025
Near the Teakettle Experimental Forest, heavier fuels in flatter terrain will continue to smolder with occasional flare-ups.
—Ca Wildfire Bot, Sacbee.com, 2 Sep. 2025
The shoot was impacted nonetheless by a flare-up in tensions between Iran and Israel – after the latter killed a number of top military officials in an airstrike on the Iranian consulate in Damascus in April 2024.
—Melanie Goodfellow, Deadline, 2 Sep. 2025
Pearce has been living with the heart condition for nearly five years and has been experiencing flare-ups since 2020.
—Lauryn Overhultz, FOXNews.com, 30 Aug. 2025
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 9 Sep. 2025.
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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