What does intrusion mean?

Definitions for intrusion
ɪnˈtru ʒənin·tru·sion

This dictionary definitions page includes all the possible meanings, example usage and translations of the word intrusion.

Princeton's WordNet

  1. invasion, encroachment, intrusionnoun

    any entry into an area not previously occupied

    "an invasion of tourists"; "an invasion of locusts"

  2. intrusionnoun

    entrance by force or without permission or welcome

  3. intrusionnoun

    the forcing of molten rock into fissures or between strata of an earlier rock formation

  4. intrusionnoun

    rock produced by an intrusive process

  5. trespass, encroachment, violation, intrusion, usurpationnoun

    entry to another's property without right or permission


  1. intrusionnoun

    The forcible inclusion or entry of an external group or individual; the act of intruding.

    He viewed sales calls as an unwelcome intrusion.

Samuel Johnson's Dictionary

  1. Intrusionnoun

    Etymology: intrusion, French; intrusio, Latin.

    It must raise more substantial superstructions, and fall upon very many excellent strains, which have been justled off by the intrusions of poetical fictions. Thomas Browne, Vulgar Errours.

    The separation of the parts of one body, upon the intrusion of another, and the change from rest to motion upon impulse, and the like, seem to have some connection. John Locke.

    I think myself in better plight for a lender than you are, the which hath something emboldened me to this unseasoned intrusion; for they say, if money go before, all ways do lie open. William Shakespeare.

    Frogs, lice, and flies, must all his palace fill
    With loath'd intrusion. John Milton, Paradise Lost.

    How's this, my son? Why this intrusion?
    Were not my orders that I should be private? Joseph Addison, Cato.

    I may close, after so long an intrusion upon your meditations. William Wake, Preparation for Death.

    It will be said, I handle an art no way suitable either to my employment or fortune, and so stand charged with intrusion and impertinency. Henry Wotton.


  1. Intrusion

    In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and compositions, illustrated by examples like the Palisades Sill of New York and New Jersey; the Henry Mountains of Utah; the Bushveld Igneous Complex of South Africa; Shiprock in New Mexico; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California.Because the solid country rock into which magma intrudes is an excellent insulator, cooling of the magma is extremely slow, and intrusive igneous rock is coarse-grained (phaneritic). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz, alkali feldspar, plagioclase, and feldspathoid is particularly important in classifying intrusive igneous rocks.Intrusions must displace existing country rock to make room for themselves. The question of how this takes place is called the room problem, and it remains a subject of active investigation for many kinds of intrusions.The term pluton is poorly defined, but has been used to describe an intrusion emplaced at great depth; as a synonym for all igneous intrusions; as a dustbin category for intrusions whose size or character are not well determined; or as a name for a very large intrusion or for a crystallized magma chamber. A pluton that has intruded and obscured the contact between a terrane and adjacent rock is called a stitching pluton.


  1. intrusion

    Intrusion is the act of entering or interrupting a place, situation, or condition without invitation, permission or welcome; often causing disruption or inconvenience. It can also refer to the unwanted or harmful entry into a computer system, breaching its security measures, in the context of cybersecurity.

Webster Dictionary

  1. Intrusionnoun

    the act of intruding, or of forcing in; especially, the forcing (one's self) into a place without right or welcome; encroachment

  2. Intrusionnoun

    the penetrating of one rock, while in a plastic or metal state, into the cavities of another

  3. Intrusionnoun

    the entry of a stranger, after a particular estate or freehold is determined, before the person who holds in remainder or reversion has taken possession

  4. Intrusionnoun

    the settlement of a minister over 3 congregation without their consent

  5. Etymology: [Cf. F. intrusion. See Intrude.]


  1. Intrusion

    An intrusion is liquid rock that forms under Earth's surface. Magma from under the surface is slowly pushed up from deep within the earth into any cracks or spaces it can find, sometimes pushing existing country rock out of the way, a process that can take millions of years. As the rock slowly cools into a solid, the different parts of the magma crystallize into minerals. Many mountain ranges, such as the Sierra Nevada in California, are formed mostly by intrusive rock, large granite formations. Intrusions are one of the two ways igneous rock can form; the other is extrusive, that is, a volcanic eruption or similar event. Technically speaking, an intrusion is any formation of intrusive igneous rock; rock formed from magma that cools and solidifies within the crust of the planet. In contrast, an extrusion consists of extrusive rock; rock formed above the surface of the crust. Intrusions vary widely, from mountain-range-sized batholiths to thin veinlike fracture fillings of aplite or pegmatite. When exposed by erosion, these cores called batholiths may occupy huge areas of Earth's surface. Large bodies of magma that solidify underground before they reach the surface of the crust are called plutons.

Dictionary of Military and Associated Terms

  1. intrusion

    Movement of a unit or force within another nation

How to pronounce intrusion?

How to say intrusion in sign language?


  1. Chaldean Numerology

    The numerical value of intrusion in Chaldean Numerology is: 7

  2. Pythagorean Numerology

    The numerical value of intrusion in Pythagorean Numerology is: 4

Examples of intrusion in a Sentence

  1. Manhattan US attorney:

    With today's plea, Tyurin's global reign of computer intrusion is over and Andrei Tyurin faces significant time in a Manhattan US attorney prison for Andrei Tyurin crimes.

  2. Marjorie Dannenfelser:

    In Montana, pro-abortion forces ranTV adscharacterizing the initiative as an ‘an extreme, harmful government intrusion into medical care,’ when all the initiative would do is provide the same level of care to an infant who survived an abortion as you would to an infant born early in pregnancy. If Montana voters knew the truth about what the initiative would actually do, it would have passed overwhelmingly. Our side must do a better job raising the resources needed to go toe-to-toe with the heavily funded abortion industry to arm voters with the truth.

  3. Harry Browne:

    The income tax is the biggest single intrusion suffered by the American people. It forces every worker to be a bookkeeper, to open his records to the government, to explain his expenses, to fear conviction for a harmless accounting error. Compliance wastes billions of dollars. It penalizes savings and creates an enormous drag on the U.S. economy. It is incompatible with a free society, and we aren’t libertarians if we tolerate it.

  4. Nancy Bray:

    Without that secondary dune line, we could have saltwater intrusion at the launch pad.

  5. Sidney Powell:

    We are here now today stop further impermissible intrusion into the sole power of the executive branch.

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Translations for intrusion

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"intrusion." Definitions.net. STANDS4 LLC, 2024. Web. 26 May 2024. <https://www.definitions.net/definition/intrusion>.

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    an unincorporated business owned by a single person who is responsible for its liabilities and entitled to its profits
    A incumbent
    B contagious
    C proprietary
    D adscripted

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