invasion

noun

in·​va·​sion in-ˈvā-zhən How to pronounce invasion (audio)
Synonyms of invasionnext
1
: an act of invading
especially : incursion of an army for conquest or plunder
2
: the incoming or spread of something usually hurtful

Synonyms of invasion

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Examples of invasion in a Sentence

The enemy launched an invasion. The people live under a constant threat of invasion. The town is gearing up for the annual tourist invasion. protecting the house from insect invasion
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Almost constant air raids in Kyiv have now reached their third day, choking the economy in the Ukrainian capital and severely disrupting civilian life more than 4½ years after Russia’s full-scale invasion of its neighbor. — ABC News, 29 Aug. 2026 The 1990 version of Days of Thunder featured Cruise as Trickle, staging something of an invasion into what was then a largely Southern sport after arriving from the world of open-wheel racing. — Greg Engle, Forbes.com, 29 Aug. 2026 It’s backed up by deployment of battlefield veterans from the war in Ukraine into schools and kindergartens to speak to children in support of President Vladimir Putin’s decision to launch the 2022 full-scale invasion. — Bloomberg, Fortune, 29 Aug. 2026 The invasion has raised European willingness to spend more on defense, and the fighting has badly degraded Russia’s armed forces. — Jennifer Kavanagh, Foreign Affairs, 28 Aug. 2026 See All Example Sentences for invasion

Word History

Etymology

Middle English invasioun "assault, attack," borrowed from Anglo-French invasion, envasioun, borrowed from Late Latin invāsiōn-, invāsiō "attack, taking possession by violence," from Latin invādere "to enter with hostile intent, assault, attack" + -tiōn-, -tiō, suffix of verbal action — more at invade

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of invasion was in the 15th century

Phrases Containing invasion

Rhymes for invasion

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Browse Nearby Words

invaried
invasion
invasionary
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Cite this Entry

“Invasion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/invasion. Accessed 1 Sep. 2026.

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Kids Definition

invasion

noun
in·​va·​sion in-ˈvā-zhən How to pronounce invasion (audio)
: an act of invading
especially : entrance of an army into a country for conquest

Medical Definition

invasion

noun
in·​va·​sion in-ˈvā-zhən How to pronounce invasion (audio)
: the act of invading: as
a
: the penetration of the body of a host by a microorganism
b
: the spread and multiplication of a pathogenic microorganism or of malignant cells in the body of a host

Legal Definition

invasion

noun
in·​va·​sion in-ˈvā-zhən How to pronounce invasion (audio)
: the act of or an instance of invading
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