invasion

/ɪnˈveɪʒən/

/ɪnˈveɪʒən/

Other forms: invasions

An invasion is the movement of an army into a region, usually in a hostile attack that's part of a war or conflict. World history is full of descriptions of invasions.

One country's army plundering or taking over a city or piece of land in another country is an invasion. You can call other mass movements invasions as well, like a horrifying invasion of your kitchen by cockroaches, or the invasion of a stadium by excited soccer fans. A common phrase is "invasion of privacy," which means an unfair intrusion into someone's personal space or private information.

Definitions of invasion

1. noun

   any entry into an area not previously occupied
   “an invasion of tourists”

   “an invasion of locusts”

   synonyms: encroachment, intrusion

   type of:

   entering, entrance

   a movement into or inward
2. noun

   the act of invading; the act of an army that invades for conquest or plunder
   types:

   inroad

   an invasion or hostile attack

   type of:

   incursion, penetration

   an attack that penetrates into enemy territory
3. noun

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

   type of:

   spread, spreading

   process or result of distributing or extending over a wide expanse of space