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
The latest flare-up has underscored the stumbling blocks to a lasting peace.
—
Jana Choukeir, USA Today, 29 Oct. 2025
Vance says Gaza ceasefire holding despite flare-ups US Vice President JD Vance said on a visit to Israel the fragile ceasefire with Hamas was holding, despite accusations by each side that the other had violated the deal.
—Ben Smith, semafor.com, 24 Oct. 2025
The truce holds, with many steps ahead The Gaza ceasefire has largely held aside from a flare-up in fighting last Sunday that left two Israeli soldiers and more than 40 Palestinians dead.
—NPR, 22 Oct. 2025
Ongoing sleep disruption raises the risk of depression, suicidal thoughts and flare-ups of conditions like bipolar disorder and schizophrenia.
—Joanna Fong-Isariyawongse, The Conversation, 21 Oct. 2025
See All Example Sentences for flare-up
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Jana Choukeir, USA Today, 29 Oct. 2025
Vance says Gaza ceasefire holding despite flare-ups US Vice President JD Vance said on a visit to Israel the fragile ceasefire with Hamas was holding, despite accusations by each side that the other had violated the deal.
—Ben Smith, semafor.com, 24 Oct. 2025
The truce holds, with many steps ahead The Gaza ceasefire has largely held aside from a flare-up in fighting last Sunday that left two Israeli soldiers and more than 40 Palestinians dead.
—NPR, 22 Oct. 2025
Ongoing sleep disruption raises the risk of depression, suicidal thoughts and flare-ups of conditions like bipolar disorder and schizophrenia.
—Joanna Fong-Isariyawongse, The Conversation, 21 Oct. 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 31 Oct. 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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