incursion

American  

[in-kur-zhuhn, -shuhn] / ɪnˈkɜr ʒən, -ʃən /

noun

1. a hostile entrance into or invasion of a place or territory, especially a sudden one; raid.

   The bandits made brief incursions on the village.

   Synonyms:

   attack, foray, sortie

2. a harmful inroad.

3. a running in.

   the incursion of sea water.

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incursion British  

/ ɪnˈkɜːsɪv, ɪnˈkɜːʃən /

noun

1. a sudden invasion, attack, or raid

2. the act of running or leaking into; penetration

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Other Word Forms

• incursive
  adjective

Etymology

Origin of incursion

1400–50; late Middle English < Latin incursiōn- (stem of incursiō ) raid, equivalent to incurs ( us ) (past participle of incurrere to incur ) + -iōn- -ion; see excursion

Explanation

When an army crosses a border into another country for battle, they are making an incursion into enemy territory. An incursion is an invasion as well as an attack. Incursion can also be used to describe other things that rush in like an army such as an invasive species into a new region or floodwaters entering your home. When an airplane heads onto a runway it is not supposed to land on, risking airport safety, it is known as a runway incursion. And an incursion of cold air could make September feel like December.

Example Sentences

Seoul initially denied any official role in the January drone incursion -- with authorities suggesting it was the work of civilians -- but Lee said a probe had revealed government officials had been involved.

From Barron's • Apr. 6, 2026

Completely marginalized during the administration’s Venezuela incursion, she was not even being invited to the White House Situation Room to observe the operation.

From Salon • Mar. 22, 2026

At Tel Aviv’s Dizengoff Square, cafes are crowded with customers, ready on a moment’s notice to put down their coffee cups and file calmly toward the nearest bunker in the event of an air incursion.

From The Wall Street Journal • Mar. 15, 2026

The military told all residents of a huge swathe of southern Lebanon near the Israeli border to leave on Wednesday, ahead of a much-anticipated ground incursion.

From BBC • Mar. 5, 2026

I put the blind back to how it was, checked I'd left no other traces of my incursion, slipped out, and flew downstairs to see who it was.

From "Black Swan Green" by David Mitchell

Related Words

• aggression
• attack
• foray
• infiltration
• inroad
• intrusion
• penetration
• raid