infiltrate

[ in-fil-treyt, in-fil-treyt ]

/ ɪnˈfɪl treɪt, ˈɪn fɪlˌtreɪt /

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See synonyms for: infiltrate / infiltrated / infiltrating / infiltrator on Thesaurus.com

verb (used with object), in·fil·trat·ed, in·fil·trat·ing.

to filter into or through; permeate.

to cause to pass in by filtering.

to move into (an organization, country, territory, or the like) surreptitiously and gradually, especially with hostile intent: The troops infiltrated the enemy lines.

to pass a small number of (soldiers, spies, or the like) into a territory or organization clandestinely and with hostile or subversive intent: The intelligence agency infiltrated three spies into the neighboring country.

verb (used without object), in·fil·trat·ed, in·fil·trat·ing.

to pass into or through a substance, place, etc., by or as by filtering.

Pathology. to penetrate tissue spaces or cells.

noun

something that infiltrates.

Pathology. any substance penetrating tissues or cells and forming a morbid accumulation.

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Origin of infiltrate

First recorded in 1750–60; in-² + filtrate

OTHER WORDS FROM infiltrate

in·fil·tra·tive

[in-fil-trey-tiv, in-fil-truh-], /ˈɪn fɪlˌtreɪ tɪv, ɪnˈfɪl trə-/, adjectivein·fil·tra·tor

[in-fil-trey-ter, in-fil-trey-], /ˈɪn fɪlˌtreɪ tər, ɪnˈfɪl treɪ-/, nounre·in·fil·trate, verb, re·in·fil·trat·ed, re·in·fil·trat·ing.un·in·fil·trat·ed, adjective

Words nearby infiltrate

infielder, infield hit, infield out, infighting, infill, infiltrate, infiltration, infiltration capacity, infiltration gallery, infiltrator, infiltrometer

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use infiltrate in a sentence

In 2008 Cromartie talked to The Gathering about the need to “infiltrate” secular media.
The $1-Billion-a-Year Right-Wing Conspiracy You Haven’t Heard Of|Jay Michaelson|September 25, 2014|DAILY BEAST
I suppose we could infiltrate the government and do nothing.
Up To A Point: My Problem With People Who Agree With Me|P. J. O’Rourke|July 20, 2014|DAILY BEAST
Police sources confirm that the Millers conspired to infiltrate an unidentified court building and execute public officials.
Hatriot Politics Created the Las Vegas Killers|John Avlon|June 10, 2014|DAILY BEAST
North Korean special forces troops would infiltrate the devices into South Korea and use them against strategic targets.
Smoke Rings, Mystery Backpacks and Gun-Toting Robots: The Weird Wartech of the Korean Conflict|Kyle Mizokami|April 3, 2014|DAILY BEAST

But she was also having daily conversations with her OSI handlers about which drug rings she should try to infiltrate.
Spies, Lies, and Rape in the Air Force: An Undercover Agent's Story|Jacob Siegel|March 4, 2014|DAILY BEAST
If it were his command hed have a sentry up there, watching for troops trying to infiltrate into the command area.
Second Variety|Philip Kindred Dick
Was there any time when your organization drew up a list of organizations, of other organizations, that it wanted to infiltrate?
Warren Commission (5 of 26): Hearings Vol. V (of 15)|The President's Commission on the Assassination of President Kennedy
We had planned to infiltrate these various rightwing organizations.
Warren Commission (5 of 26): Hearings Vol. V (of 15)|The President's Commission on the Assassination of President Kennedy
To what extent were you able to infiltrate, as you call it, General Walker's group?
Warren Commission (5 of 26): Hearings Vol. V (of 15)|The President's Commission on the Assassination of President Kennedy
How did you infiltrate the Young Americans for Freedom, and what led you to believe you had been successful?
Warren Commission (5 of 26): Hearings Vol. V (of 15)|The President's Commission on the Assassination of President Kennedy

British Dictionary definitions for infiltrate

infiltrate

/ (ˈɪnfɪlˌtreɪt) /

verb

to undergo or cause to undergo the process in which a fluid passes into the pores or interstices of a solid; permeate

military to pass undetected through (an enemy-held line or position)

to gain or cause to gain entrance or access surreptitiouslythey infiltrated the party structure

noun

something that infiltrates

pathol any substance that passes into and accumulates within cells, tissues, or organs

pathol a local anaesthetic solution injected into the tissues to cause local anaesthesia

Derived forms of infiltrate

infiltration, nouninfiltrative, adjectiveinfiltrator, noun

Word Origin for infiltrate

C18: from in- ² + filtrate

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

infiltrate

Origin of infiltrate

OTHER WORDS FROM infiltrate

Words nearby infiltrate

Words related to infiltrate

How to use infiltrate in a sentence

British Dictionary definitions for infiltrate

Derived forms of infiltrate

Word Origin for infiltrate