Dictionary.com
Thesaurus.com
Synonyms

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.
incursion British  
/ ɪnˈkɜːsɪv, ɪnˈkɜːʃən /

noun

  1. a sudden invasion, attack, or raid

  2. the act of running or leaking into; penetration

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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; 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.

Keep Reading on Vocabulary.com

Vocabulary lists containing incursion

Lord of the Flies

Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!

The Son of Neptune

Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!

Texas v. Johnson (1989)

Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The AEA allows the government to detain and deport citizens of hostile foreign nations in times of war or during an "invasion or predatory incursion."

From Barron's • Mar. 24, 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

But Aoun described it as a deliberate ambush set for Lebanon and its army, designed to draw the Israeli military into another incursion.

From BBC • Mar. 10, 2026

This was his first incursion into management circles.

From "The God of Small Things" by Arundhati Roy

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.