irrupt vs flare up

irrupt and flare up both are verbs.

Word	Noun	Adjective	Verb	Adverb
irrupt	No	No	Yes	No
flare up	No	No	Yes	No

As verbs, irrupt and flare up are synonyms defined as:

Other synonyms of irrupt include break open, burst out, erupt, flare.

irrupt (verb)	flare up (verb)
increase rapidly and in an uncontrolled manner	erupt or intensify suddenly
erupt or intensify suddenly	ignite quickly and suddenly, especially after having died down
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