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

Khutor added that the company’s experience developing drones during Russia’s invasion of Ukraine has positioned it to meet growing international demand. — Maria Mocerino, Interesting Engineering, 4 July 2026

When the Martians attack in George Pal's 1953 movie, the US army — unsurprisingly — drop an atomic bomb on their invasion fleet, but they're left unscathed thanks to their powerful forcefields. — Richard Edwards, Space.com, 4 July 2026

Almost daily long-range attacks on Russian oil facilities have created a fuel crisis and heaped political pressure on the Kremlin as its all-out invasion of Ukraine stretches into its fifth year. — ABC News, 4 July 2026

By way of example, Bäte notes that Allianz did not fully foresee the speed with which interest rates rose after Russia’s full invasion of Ukraine in 2022. — Andrew Edgecliffe-Johnson, semafor.com, 3 July 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