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

Meanwhile, Russian President Vladimir Putin claimed Tuesday that Russian forces have extended their gains in Ukraine’s eastern Donbas region, whose capture Moscow has made one of the goals of its invasion. —Hanna Arhirova, Los Angeles Times, 10 Mar. 2026

At the same time, since World War II, Moscow has initiated around nine or ten military invasions in other countries. —Hanlu Zhang, Artforum, 10 Mar. 2026

Russia was accused of using cluster bombs in its 2022 full-scale invasion of Ukraine, a charge Moscow denied. —Melanie Lidman, Chicago Tribune, 10 Mar. 2026

Middle-income countries can learn an important lesson from this moment, similar to the one Europe learned in 2022 following the invasion of Ukraine. —Tim McDonnell, semafor.com, 10 Mar. 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