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Synonyms

intrusion

American  
[in-troo-zhuhn] / ɪnˈtru ʒən /

noun

  1. an act or instance of intruding.

  2. the state of being intruded.

  3. Law.

    1. an illegal act of entering, seizing, or taking possession of another's property.

    2. a wrongful entry after the determination of a particular estate, made before the remainderman or reversioner has entered.

  4. Geology.

    1. emplacement of molten rock in preexisting rock.

    2. plutonic rock emplaced in this manner.

    3. a process analogous to magmatic intrusion, as the injection of a plug of salt into sedimentary rocks.

    4. the matter forced in.


intrusion British  
/ ɪnˈtruːʒən /

noun

  1. the act or an instance of intruding; an unwelcome visit, interjection, etc

    an intrusion on one's privacy

    1. the movement of magma from within the earth's crust into spaces in the overlying strata to form igneous rock

    2. any igneous rock formed in this way

  2. property law an unlawful entry onto land by a stranger after determination of a particular estate of freehold and before the remainderman or reversioner has made entry

"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

intrusion Scientific  
/ ĭn-tro̅o̅zhən /
  1. The movement of magma through cracks in underground rocks within the Earth, usually in an upward direction.

  2. ◆ Rocks that form from the underground cooling of magma are generally coarse-grained (because they cool slowly so that large crystals have time to grow) and are called intrusive rocks.

  3. Compare extrusion


Other Word Forms

Etymology

Origin of intrusion

1250–1300; Middle English < Medieval Latin intrūsiōn- (stem of intrūsiō ), equivalent to Latin intrūs ( us ), past participle of intrūdere to intrude (equivalent to intrūd- verb stem + -tus past participle suffix, with dt < s ) + -iōn- -ion

Explanation

An intrusion is a deliberate move into someone else's territory — either literal or figurative. When your sister interrupts your conversation with that girl from math class, that's an intrusion. If someone breaks into your home, that's also an intrusion. First used in the late 14th century, the noun intrusion derives from the Latin word intrudere, which combines the prefix in-, meaning "in," and trudere, meaning "to thrust, push." If someone reads your diary, that's considered an intrusion of privacy. Ordering a Muslim woman to take off her veil would be considered an intrusion on religious beliefs. You may remember intrusion used in science class to describe molten rock that forms in an earlier rock formation.

Keep Reading on Vocabulary.com

Vocabulary lists containing intrusion

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 team released the results of their study in the recent report, Saltwater Intrusion Vulnerability Assessment in Plymouth, MA.

From Science Daily • Nov. 2, 2023

Intrusion co-founder Joe Head said Congress needs to develop ways to fund new cyber programs and responses to new digital breaches while operating under stopgap spending legislation.

From Washington Times • Sep. 19, 2023

He's become a go-to-person if there is an problem in the Intrusion Prevention System, which monitors the network for unauthorised activities.

From BBC • Jul. 27, 2023

Sept. 22 "Confessions of an Invisible Girl" "Dear White People" Season 4 "Intrusion" "Jaguar" "Monsters Inside: The 24 Faces of Billy Milligan"

From Salon • Sep. 4, 2021

Intrusion must bring anxiety and pain, it might bring fear.

From Hidden Creek by Burt, Katharine Newlin