intrusion

noun

in·​tru·​sion in-ˈtrü-zhən How to pronounce intrusion (audio)
Synonyms of intrusionnext
1
: the act of intruding or the state of being intruded
especially : the act of wrongfully entering upon, seizing, or taking possession of the property of another
2
: the forcible entry of molten rock or magma into or between other rock formations
also : the intruded magma

Examples of intrusion in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The Justice Department did not detail the damage to the agencies or other targets from the computer intrusions. — Dan Mangan, CNBC, 26 Aug. 2026 The column argues that Sheriff Chad Bianco’s seizure of more than 650,000 Proposition 50 ballots was an unprecedented intrusion into the election process that threatened the integrity of the vote and the chain of custody for ballots. — Los Angeles Times, 25 Aug. 2026 The work includes crews searching throughout the building and conducting ongoing moisture checks to identify and address potential moisture intrusion points. — Nadine El-Bawab, ABC News, 25 Aug. 2026 The centers’ effect on the environment and intrusion on residential properties are particular areas of concern. — Claire Carter, The Washington Examiner, 21 Aug. 2026 See All Example Sentences for intrusion

Word History

Etymology

Middle English, from Anglo-French, from Medieval Latin intrusion-, intrusio, from Latin intrudere

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of intrusion was in the 15th century

Phrases Containing intrusion

Rhymes for intrusion

See All Rhymes for intrusion

Browse Nearby Words

intrudingly
intrusion
intrusive
See all Nearby Words

Cite this Entry

“Intrusion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/intrusion. Accessed 2 Sep. 2026.

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Kids Definition

intrusion

noun
in·​tru·​sion in-ˈtrü-zhən How to pronounce intrusion (audio)
1
: the act of intruding : the state of being intruded
2
: the entry by force of melted rock into or between other rock formations

Legal Definition

intrusion

noun
in·​tru·​sion in-ˈtrü-zhən How to pronounce intrusion (audio)
1
a
: the entry at common law of a stranger after a particular estate of freehold is determined before the person who holds it in remainder or reversion has taken possession
b
: the act of wrongfully entering upon, seizing, or taking possession of the property of another
2
: a trespassing on or encroachment upon something (as a right)
the Fourth Amendment demands that the showing of justification match the degree of intrusion—Berger v. New York, 388 U.S. 41 (1968)

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