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 satellite service was rolled out in Ukraine in 2022 to replace internet and communication networks damaged by Russia’s invasion of the country, quickly becoming a critical tool for both civilian and military connectivity. —Dylan Butts, CNBC, 5 Jan. 2026

The New York Times withheld some details in advance about the US Bay of Pigs invasion, and for months delayed a story on national security administration warrantless wiretapping during the Bush administration after White House officials said the story’s publication would endanger American lives. —Max Tani, semafor.com, 4 Jan. 2026

The question no one in the administration is willing to address is what is the legal authority for the invasion of Venezuela? —Reader Commentary, Baltimore Sun, 4 Jan. 2026

There were some differences back then, and there was also a claim that the Panama Canal treaties gave a legal justification for the invasion, but otherwise the arguments are very similar. —Isaac Chotiner, New Yorker, 3 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