invasion

American  

[in-vay-zhuhn] / ɪnˈveɪ ʒən /

noun

• invasions
  plural

1. an act or instance of invading or entering as an enemy, especially by an army.

2. the entrance or advent of anything troublesome or harmful, as disease.

3. entrance as if to take possession or overrun.

   the annual invasion of the resort by tourists.

4. infringement by intrusion.

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invasion British  

/ ɪnˈveɪʒən /

noun

1. the act of invading with armed forces

2. any encroachment or intrusion

   an invasion of rats

3. the onset or advent of something harmful, esp of a disease

4. pathol the spread of cancer from its point of origin into surrounding tissues

5. the movement of plants to a new area or to an area to which they are not native

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Other Word Forms

Derived Forms

• reinvasion
  noun
• preinvasion
  adjective

Inflected Forms

Nouns

• invasions
  plural

Etymology

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

Explanation

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.

Example Sentences

See Examples For:

invasion invasions

Perhaps Robinson's greatest Whitley Bay moment came in the 2010 FA Vase semi-final second leg, when his last-minute diving header in the driving rain secured a 6-5 aggregate victory over Barwell, sparking a pitch invasion.

From BBC ● Sep. 30, 2026

South Korea has in recent years emerged as a major arms exporter -- particularly since Russia's invasion of Ukraine in early 2022 -- including through a multibillion-dollar arms deal with Poland.

From Barron's ● Sep. 30, 2026

He remained one of the few journalists who continued to report inside the country after Russia's full-scale invasion of Ukraine in 2022.

From Barron's ● Sep. 30, 2026

At Ford Motor’s massive assembly plant in Hermosillo, Mexico, a persistent pigeon invasion was posing a health risk to workers, disrupting daily operations, and threatening damage to freshly painted pickup trucks and SUVs.

From The Wall Street Journal ● Sep. 27, 2026

The English rangers who had trained to fight like Highlanders were essential to Britain’s invasion of Florida in 1739.

From "An Indigenous People’s History of the United States" by Roxanne Dunbar-Ortiz

The search for the source of the medbed conspiracy took me into the world of scammers and crystals and alien invasions and broken families and sci-fi movie sets and the Arizona desert.

From Slate ● Sep. 22, 2026

In both of these misguided invasions, Americans apparently convinced themselves that Canadians essentially did not exist, at least not as a people or a nation with a shared collective identity.

From Salon ● Aug. 31, 2026

Castro is remembered by supporters as having guided Cuba through multiple crises -- US-backed invasions, embargoes, assassination plots and the intense hardship caused by the collapse of Cuba's main ally and benefactor, the Soviet Union.

From Barron's ● Aug. 11, 2026

Few examples of this genre survive from before the Japanese invasions of 1592-98.

From The Wall Street Journal ● Jun. 6, 2026

It even turned out to be crucial for the D-Day invasions.

From "The Woman All Spies Fear" by Amy Butler Greenfield

Related Words

• aggression
• assault
• breach
• incursion
• infiltration
• infringement
• intrusion
• offensive
• onslaught
• raid
• violation