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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
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Merriam-Webster unabridgedWords at Play
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Time Traveler for irruption
The first known use of irruption was circa 1540
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