[1] : The Collaborative International Dictionary of English v.0.48

irruption \irrup"tion\, n. l. irruptio: cf. f. irruption. see
   irrupted.
   1913 webster
   1. a bursting in; a sudden, violent rushing into a place; as,
      irruptions of the sea.
      1913 webster

            lest evil tidings, with too rude irruption
            hitting thy aged ear, should pierce too deep.
                                                  --milton.
      1913 webster

   2. a sudden and violent inroad, or entrance of invaders; as,
      the irruptions of the goths into italy. --addison.

   syn: invasion; incursion; inroad. see invasion.
        1913 webster
see also:
irrupted invasion 

[2] : WordNet (r) 2.0

irruption
     n 1: a sudden violent entrance; a bursting in; "the recent
          irruption of bad manners"
     2: a sudden sharp increase in the relative numbers of a
        population
     3: a sudden violent spontaneous occurrence usually of some
        undesirable condition; "the outbreak of hostilities"
        syn: outbreak, eruption
see also:
outbreak eruption 

[3] : Moby Thesaurus II by Grady Ward, 1.0

58 moby thesaurus words for "irruption":
   air attack, air raid, air strike, blaze, boarding, burst,
   convulsion, cyclone, encroachment, entrance, entrenchment,
   eruption, escalade, explosion, fire raid, fit, flare-up, foray,
   gale, gust, hurricane, impingement, imposition, incursion,
   infiltration, influx, infringement, injection, inroad, insinuation,
   interference, interjection, interloping, interposition,
   interposure, interruption, intervention, intrusion, invasion,
   obtrusion, outbreak, outburst, paroxysm, raid, razzia,
   saturation raid, scaling, seizure, shuttle raid, spasm, storm,
   tempest, tornado, trespass, trespassing, unlawful entry, upheaval,
   whirlwind

Irruption >> I Words
Irruption, definition of term: Irruption
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