invasion

noun

in·​va·​sion in-ˈvā-zhən 

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

• incursion
• raid

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

The continent has in recent years drastically cut its reliance on Russian pipeline gas following Moscow’s 2022 invasion of Ukraine, but its main source to fill the gap, Washington, has proven unreliable, making homegrown clean power all the more necessary. —Natasha Bracken, semafor.com, 27 Jan. 2026

There would be no obstacle for the further invasion of Europe if the Jewish state doesn't exist. —Amelie Botbol, FOXNews.com, 27 Jan. 2026

As in recent years, Russia representatives were not invited to the observances at Auschwitz due to the country’s invasion of Ukraine. —Vanessa Gera, Los Angeles Times, 27 Jan. 2026

His particular focus was Germany’s Rheinmetall AG, which despite being the country’s largest defense company was not seen pre-invasion as a particularly exciting bet. —Gerry Doyle, Bloomberg, 27 Jan. 2026

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

Phrases Containing invasion

• counter-invasion
• invasion of (someone's) privacy
• pre-invasion

Rhymes for invasion

• abrasion
• caucasian
• equation
• eurasian
• evasion
• occasion
• persuasion
• asian
• suasion
• athanasian

Kids Definition

invasion

noun

in·​va·​sion in-ˈvā-zhən 

: an act of invading

especially : entrance of an army into a country for conquest

Medical Definition

invasion

noun

in·​va·​sion in-ˈvā-zhən 

: 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 

: the act of or an instance of invading