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 president who relishes causing offense now takes offense at the ongoing intrusion from a ghost of his past. Tara Palmeri, Vanity Fair, 12 Feb. 2026 This increases the risk of saltwater intrusion into the aquifer — a problem already intensified by rising sea levels. Ashley Miznazi, Miami Herald, 10 Feb. 2026 Security stopped Gonzalez near the 10-yard line before turning him over to police, and according to TMZ, he was charged with trespassing and field intrusion. Tiffani Jackson, Fort Worth Star-Telegram, 10 Feb. 2026 This was bound to result in agent intrusions into homes and businesses, since there aren’t that many criminal migrants to fill such a quota each day. The Wall Street Journal, Twin Cities, 6 Feb. 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

Browse Nearby Words

Cite this Entry

“Intrusion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/intrusion. Accessed 16 Feb. 2026.

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 intrusionBerger v. New York, 388 U.S. 41 (1968)

More from Merriam-Webster on intrusion

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster