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

• 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

Officers arrested Florez at the address of the home-invasion call. —Harriet Ramos, Fort Worth Star-Telegram, 4 Oct. 2025

Later, a labor shortage, the Russian invasion of Ukraine, and resulting disruption of oil markets combined to keep prices climbing still higher. —Alexander Coolidge, Cincinnati Enquirer, 3 Oct. 2025

After 3 1/2 years of Russia's full-scale invasion of Ukraine, European countries like this one — Kyiv's backers and military suppliers — are nervous the Kremlin could bring the conflict their way. —Teri Schultz, NPR, 3 Oct. 2025

In the days after the invasion of Ukraine, thousands of people in cities across Russia protested against the military campaign. —Nina Khrushcheva, Time, 3 Oct. 2025

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