[ flair-uhp ]
See synonyms for flareup on Thesaurus.com
  1. a sudden flaring up of flame or light.

  2. a sudden outburst or intensification, as of anger or tensions.

  1. a sudden outbreak of violence, disease, or any other condition thought to be quelled, checked, or inactive.

Origin of flareup

First recorded in 1830–40; noun use of verb phrase flare up

Words Nearby flareup

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use flareup in a sentence

British Dictionary definitions for flare-up


  1. a sudden burst of fire or light

  2. informal a sudden burst of emotion or violence

verbflare up (intr, adverb)
  1. to burst suddenly into fire or light

  2. informal to burst into anger

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Idioms and Phrases with flareup


Suddenly become angry, as in She flared up at the slightest provocation. This metaphoric expression, dating from the mid-1800s, transfers a sudden burst of flame to sudden rage.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.