ir·​rup·​tion i-ˈrəp-shən How to pronounce irruption (audio)
plural irruptions
: an act or instance of irrupting: such as
: a sudden, violent, or forcible entry : a rushing or bursting in
… the assassination still feels like a primal catastrophe—an irruption of inexplicable evil as horrifying as any supernatural bogeyman.Ross Douthat
: a sudden and violent invasion
… begins not with Hitler's attack on Poland, but with the Japanese irruption into Outer Mongolia in July 1939…John Gooch
ecology : a sudden sharp increase in the relative numbers of a natural population usually associated with favorable alteration of the environment
The owl's appearance came during an irruption, a huge southward migration of snowy owls from their arctic territories that, this year, followed a successful breeding period.Scott Carroll

Examples of irruption in a Sentence

Recent Examples on the Web What is an irruption? Paul A. Smith, Journal Sentinel, 22 Nov. 2022 An irruption is a sudden change in population density. San Diego Union-Tribune, 11 Feb. 2023 This irruption of violence dovetailed with the rise of the Ku Klux Klan, which began as a social club in Tennessee and then quickly metastasized into a band of white supremacist terrorists. Marc Weingarten, Los Angeles Times, 17 Jan. 2023 Data from recent years show a winter poor as this one was followed, two years later, by the biggest irruption in generations, according to Weidensaul. Paul A. Smith, Journal Sentinel, 13 Jan. 2023 The numbers are low for the middle of November, Brady said, and suggest an irruption, in which large numbers of owls move into Wisconsin and the U.S., is unlikely this year. Paul A. Smith, Milwaukee Journal Sentinel, 21 Nov. 2021 According to Rauch, the last irruption of snowy owls in the D.C. area was in 2014, when at least four were reported. Washington Post, 10 Jan. 2022 The reasons aren’t hard to imagine: the irruption of e-commerce and changes in consumer habits. Damian Scalerandi, Forbes, 8 Sep. 2021 The exact cause of an irruption is unknown and difficult to predict, although according to the DNR in recent irruption years more owls had been spotted by this time — 84 in 2017, 82 in 2015 and 44 in 2014. Chelsey Lewis, Milwaukee Journal Sentinel, 30 Nov. 2020 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'irruption.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

circa 1540, in the meaning defined above

Time Traveler
The first known use of irruption was circa 1540

Dictionary Entries Near irruption

Cite this Entry

“Irruption.” Dictionary, Merriam-Webster, Accessed 28 Nov. 2023.

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