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.
Already postponed 24 hours, the invasion proceeded in the face of rough seas, strong winds, and low visibility in order to seize a small window in time of enormous consequence. — Marc E. Andersen, Washington Post, 21 Oct. 2026 The scale of the invasion has made control difficult, and harvester and marine economic development coordinator Eli Gladstone hopes a viable market for the crabs could help reduce their numbers. — Victoria Malloy, Time, 21 Oct. 2026 Hubbard, 74, of Michigan, had been living in eastern Ukraine for years when Russia launched its full-scale invasion in 2022. — Garrett Haake, NBC news, 21 Oct. 2026 Norwegian Prime Minister Jonas Gahr Store and Finnish President Alexander Stubb also attended the talks, which focused on ceasefire proposals to halt Russia's full-scale invasion of Ukraine. — ABC News, 21 Oct. 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 22 Oct. 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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