verb (used without object)

to break or burst in suddenly.
to manifest violent activity or emotion, as a group of persons.
(of animals) to increase suddenly in numbers through a lessening of the number of deaths.

Origin of irrupt

1850–55; < Latin irruptus; see irruption
Related formsun·ir·rupt·ed, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for irrupt


verb (intr)

to enter forcibly or suddenly
(of a plant or animal population) to enter a region suddenly and in very large numbers
(of a population) to increase suddenly and greatly
Derived Formsirruption, noun

Word Origin for irrupt

C19: from Latin irrumpere to rush into, invade, from rumpere to break, burst
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for irrupt

"to break into," 1855, back-formation from irruption or else from Latin irruptus, past participle of irrumpere (see irruption).

Online Etymology Dictionary, © 2010 Douglas Harper