intr.v. ir·rupt·ed, ir·rupt·ing, ir·rupts
1. To break or burst in: The boys irrupted into the kitchen.
2. Ecology To increase rapidly in number, especially beyond the normal range: snowy owls that irrupted southward.
[Latin irrumpere, irrupt- : in-, in; see IN-2 + rumpere, to break; see reup- in the Appendix of Indo-European roots.]
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