[in-vey-zhuh n]


an act or instance of invading or entering as an enemy, especially by an army.
the entrance or advent of anything troublesome or harmful, as disease.
entrance as if to take possession or overrun: the annual invasion of the resort by tourists.
infringement by intrusion.

Origin of invasion

1400–50; late Middle English < Late Latin invāsīon- (stem of invāsiō), equivalent to invās(us), past participle of invādere + -iōn- -ion; see invade
Related formspre·in·va·sion, adjectivere·in·va·sion, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for invasion

Contemporary Examples of invasion

Historical Examples of invasion

  • On the invasion of William, as we have seen, it was in the possession of Edwin, sovereign of Deira.

    The Grand Old Man

    Richard B. Cook

  • Napoleon was silent a moment, as if protesting against this invasion of his privacy.

  • This was at a moment when all England was in arms, in anticipation of an invasion from France.

    Ned Myers

    James Fenimore Cooper

  • All those who could bear a musket were gone to meet the invasion.

    In the Valley

    Harold Frederic

  • I rubbed my sleepy eyes, and could not quite understand the meaning of this invasion.

    My Double Life

    Sarah Bernhardt

British Dictionary definitions for invasion



the act of invading with armed forces
any encroachment or intrusionan invasion of rats
the onset or advent of something harmful, esp of a disease
pathol the spread of cancer from its point of origin into surrounding tissues
the movement of plants to a new area or to an area to which they are not native
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 invasion

mid-15c., from Old French invasion "invasion, attack, assaut" (12c.), from Late Latin invasionem (nominative invasio) "an attack, invasion," noun of action from past participle stem of Latin invadere "go into, fall upon, attack, invade," from in- "in" (see in- (2)) + vadere "go, walk" (see vamoose).

Online Etymology Dictionary, © 2010 Douglas Harper