ir·​rup·​tion | \ i-ˈrəp-shən How to pronounce irruption (audio) \
plural irruptions

Definition of irruption

: an act or instance of irrupting: such as
a : 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
b : 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
c 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

Keep scrolling for more

Examples of irruption in a Sentence

Recent Examples on the Web The President wants to make the elections a referendum on himself and on immigration, but his irruptions are drowning out other GOP messages like the growing economy and tax reform. The Editorial Board, WSJ, "The Wisconsin Canary," 4 Apr. 2018 During an irruption, younger owls strike out on their own in search of food and space. Kat Eschner, Smithsonian, "A Boom of Snowy Owls Masks a Host of Climate Threats," 8 Feb. 2018 The greater number of birds is referred to as an irruption, which usually leads to more of the owls flying farther south in the winter in search of food. Mari A. Schaefer,, "Snowy owls calling Philadelphia International Airport their winter home," 5 Mar. 2018 These owls are migrating from northern Canada during what is called an irruption, which the owls cycle through every four to five years. Sarah Bowman, Indianapolis Star, "Snowy owl rescued in northern Indiana dies, second owl on the mend," 8 Dec. 2017 The only way to escape her father’s virtual suicide pact is through violence, and the novel culminates in an irruption of gunplay. Sam Sacks, WSJ, "The Best New Fiction," 25 Aug. 2017

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

See More

First Known Use of irruption

circa 1540, in the meaning defined above

Keep scrolling for more

Learn More about irruption

Time Traveler for irruption

Time Traveler

The first known use of irruption was circa 1540

See more words from the same year

Statistics for irruption

Cite this Entry

“Irruption.” Dictionary, Merriam-Webster, Accessed 28 May. 2020.

More from Merriam-Webster on irruption

Thesaurus: All synonyms and antonyms for irruption

Britannica English: Translation of irruption for Arabic Speakers

Comments on irruption

What made you want to look up irruption? Please tell us where you read or heard it (including the quote, if possible).


See Definitions and Examples »

Get Word of the Day daily email!

Test Your Vocabulary

Obscure Shapes

  • a pile of three dimensional shapes in green
  • Something that is ooid is shaped like:
Spell It

Can you spell these 10 commonly misspelled words?

Syn City

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!