invasion (n.)

  1. the act of invading; the act of an army that invades for conquest or plunder

  2. any entry into an area not previously occupied; an invasion of tourists; an invasion of locusts

    [ Syn: encroachment , intrusion ]

  3. (pathology) the spread of pathogenic microorganisms or malignant cells to new sites in the body; the tumor's invasion of surrounding structures'

The dictionary is based on the WordNet Electronic Lexical Database.
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