irruption

noun ir·rup·tion \ i-ˈrəp-shən \

Definition of irruption

plural irruptions

: 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

Recent Examples of irruption from 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, Philly.com, "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.