Lewis Short
irruptÄo (noun F) : irrumpo
* A breaking or bursting in, an irruption.
* In gen.: irruptionem facere in popinam,Plaut. Poen. prol. 42: ferarum,Plin. Pan. 81: belli,Flor. 2, 12, 5: luminis,Pall. 10, 17: aquarum,Sen. Q. N. 3, 30, 5.
* Esp., as milit. t. t., an invasion, incursion, sally: hostis,Suet. Tib. 6: etiamsi irruptio facta nulla sit,Cic. de Imp. Pomp. 6, 15: Gallorum, Aug. Civ. Dei, 3, 31.
Charlton T. Lewis, Charles Short, A Latin Dictionary