flare up
[verb]
Synonyms: lose one's temper, blow one's top (informal), boil over, explode, fly off the handle (informal), throw a tantrum

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Contrasted words: calm (down), cool (off or down), simmer down
Related Idioms: blow one's stack (or top or lid), fly into a passion, fly off the handle

[TahlilGaran] English Synonym Dictionary ▲

ˈflare-up noun [countable]

1. a situation in which someone suddenly becomes angry or violent:
Apart from one or two flare-ups the match went fairly smoothly.

2. a situation in which someone suddenly has problems because of a disease or illness after not having any problems for a long time:
a flare-up of her arthritis

[TahlilGaran] Dictionary of Contemporary English ▲

flare up
to happen suddenly.
Severe thunderstorms flare up there at almost any time during the summer.

You may not feel like chopping vegetables when the pain in your hands flares up.

Etymology: based on the literal meaning of flare up (= to suddenly burn brightly)

[TahlilGaran] English Idioms Dictionary ▲

flare up
to become suddenly angry, to begin again suddenly (an illness or a disease)
The fighting flared up again after the United Nations soldiers left the town.

My mother's skin problem flared up when she started to use the new laundry soap.

[TahlilGaran] English Idioms Dictionary ▲

flare up(1)
v.
1. To burn brightly for a short time especially after having died down.
The fire flared up again and then died.
2. To become suddenly angry.
The mayor flared up at the reporter's remark.
The mother flared up at her children.
3. To begin again suddenly, especially for a short time after a quiet time.
Mr. Gray's arthritis flared up sometimes.
Even after they had conquered the country, revolts sometimes flared up.

[TahlilGaran] English Idioms Dictionary ▲

flare-up(2)
n. The reoccurrence of an infection or an armed conflict.
He had a flare-up of his arthritis.
There was a bad flare-up of hostilities in some countries.

[TahlilGaran] English Idioms Dictionary ▲