intrusion

noun

in·​tru·​sion in-ˈtrü-zhən 

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

What ultimately proved effective at stopping this was not necessarily the convergence of technology and lessons learned, but a proactive rather than reactive strategy towards stopping intrusions. — Zita Ballinger Fletcher, Forbes.com, 30 July 2026

Hugging Face detected and contained the intrusion on its own days before OpenAI connected the activity to its internal testing, and had already reported it to law enforcement. — Beatrice Nolan, Fortune, 29 July 2026

That is an unprecedented intrusion into the private sector and the operations of private businesses. — Morgan Chalfant, semafor.com, 24 July 2026

Hugging Face said its security team and AI agents detected and stopped the intrusion, then began containing the breach and reconstructing what happened. — Ethan Baron, Mercury News, 23 July 2026

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

Phrases Containing intrusion

• anti-intrusion

Rhymes for intrusion

• allusion
• collusion
• conclusion
• confusion
• contusion
• delusion
• diffusion
• effusion
• exclusion
• extrusion
• illusion
• inclusion

Kids Definition

intrusion

noun

in·​tru·​sion in-ˈtrü-zhən 

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 

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)