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 soldiers served under Napoleon during his disastrous invasion of Russia in the winter of 1812. —Andrea Margolis, FOXNews.com, 15 Nov. 2025

Russia’s invasion of Ukraine in early 2022 pushed up energy and food costs, and consumer prices reached a four-decade high that June. —Josh Boak, Fortune, 15 Nov. 2025

In the eyes of the judge, if the Nord Stream blasts were a Ukrainian act of sabotage, that would be a justified response to an unprovoked invasion. —Joseph Ataman, CNN Money, 15 Nov. 2025

Wright built his career by riffing on pop culture with the understanding and appreciation of a real geek, mocking a pretentious art scene with a reference to Resident Evil 2 in Spaced, or using a Body Snatchers–style invasion to explore aging in The World’s End. —Alison Willmore, Vulture, 14 Nov. 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