ir·​rupt | \ i-ˈrəpt How to pronounce irrupt (audio) \
irrupted; irrupting; irrupts

Definition of irrupt

intransitive verb

1 : to rush in forcibly or violently
2 of a natural population : to undergo a sudden upsurge in numbers especially when natural ecological balances and checks are disturbed
3 : erupt sense 1c the crowd irrupted in a fervor of patriotismTime

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Did You Know?

Irrupt and "erupt" have existed as discrete words since the 1800s. Both are descendants of the Latin verb rumpere, which means "to break," but "irrupt" has affixed to it the prefix ir- (in the sense "into") while "erupt" begins with the prefix e- (meaning "out"). So "to irrupt" was originally to rush in, and "to erupt" was to burst out. But it's sometimes hard to distinguish the precise direction of a violent rush, and "irrupt" came to be used as a synonym of "erupt" in the senses "to become active or violent especially suddenly" and "to break forth," as in our example sentence.

Examples of irrupt in a Sentence

Recent Examples on the Web Much of the excitement comes from the opportunity to see migrants such as snowy owls and winter finches irrupting from the north, as well as southern species expanding their winter ranges northward. James F. Mccarty,, "Christmas Bird Counts to document the snowy owl irruption underway in Northeast Ohio (photos)," 8 Dec. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'irrupt.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of irrupt

1886, in the meaning defined at sense 1

History and Etymology for irrupt

Latin irruptus, past participle of irrumpere, from in- + rumpere to break — more at reave

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Time Traveler for irrupt

Time Traveler

The first known use of irrupt was in 1886

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Cite this Entry

“Irrupt.” Dictionary, Merriam-Webster, Accessed 20 Oct. 2020.

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