infiltrate

verb
in·​fil·​trate | \ in-ˈfil-ˌtrāt How to pronounce infiltrate (audio) , ˈin-(ˌ)fil- How to pronounce infiltrate (audio) \
infiltrated; infiltrating

Definition of infiltrate

transitive verb

1 : to cause (something, such as a liquid) to permeate something by penetrating its pores or interstices
2 : to pass into or through (a substance) by filtering or permeating
3 : to pass (troops) singly or in small groups through gaps in the enemy line
4 : to enter or become established in gradually or unobtrusively usually for subversive purposes the intelligence staff had been infiltrated by spies

intransitive verb

: to enter, permeate, or pass through a substance or area by filtering or by insinuating gradually

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Other Words from infiltrate

infiltrate noun
infiltration \ ˌin-​(ˌ)fil-​ˈtrā-​shən How to pronounce infiltration (audio) \ noun
infiltrative \ ˈin-​(ˌ)fil-​ˌtrā-​tiv How to pronounce infiltrative (audio) , in-​ˈfil-​trə-​ \ adjective
infiltrator \ in-​ˈfil-​ˌtrā-​tər How to pronounce infiltrator (audio) , ˈin-​(ˌ)fil-​ How to pronounce infiltrator (audio) \ noun

Examples of infiltrate in a Sentence

The gang was infiltrated by undercover agents. Attempts to infiltrate undercover agents into the gang have failed. Water can easily infiltrate the soil.
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Recent Examples on the Web Befriended by two artsy outcasts, the three hatch a plot for Cady to infiltrate the popular girls’ clique and wreak havoc on the high school social order. cleveland, "National tour of ‘Mean Girls’ at Playhouse Square is entertaining, but it’s not quite ‘fetch’," 6 Dec. 2019 According to a nine-month investigation by Louisville Courier-Journal, El Mencho is infiltrating cities and towns across America and has a presence in at least 35 states. Fox News, "A Mexican drug kingpin you've never heard of is infiltrating small-town America," 26 Nov. 2019 Paranoid rhetoric throughout American history, Hofstadter wrote, told an apocalyptic story of a network of agents determined to infiltrate and undermine the nation. Jennifer Mercieca, The Conversation, "Law-and-order or conspiracy? How political parties frame the impeachment battle will help decide Trump’s fate," 12 Nov. 2019 Maria Butina, a gun rights activist who sought to infiltrate conservative U.S. political groups and promote Russia’s agenda around the time that Donald Trump rose to power, was released Friday from a low-security facility in Florida. BostonGlobe.com, "Maria Butina, a gun rights activist who sought to infiltrate conservative U.S. political groups and promote Russia’s agenda around the time that Donald Trump rose to power, was released Friday from a low-security facility in Florida. She had been in custody since her arrest in July 2018.," 26 Oct. 2019 Authorities had deployed more aggressive tactics during the weekend protests, with riot police videotaped beating demonstrators in subway stations and officers going undercover to infiltrate the group and make arrests. Shirley Li, Fortune, "Hong Kong Airport Cancels All Flights As Protests Prompt Biggest Disruption Yet," 12 Aug. 2019 Hailed as one of the best movies of the year, Bong Joon-ho’s Parasite is rife with class tensions, chronicling the poor Kim family’s attempt to infiltrate the rich Park family’s household one person at a time. Christian Holub, EW.com, "Parasite director Bong Joon-ho explains the art of controlled chaos," 12 Nov. 2019 China’s lawless efforts to infiltrate the American academy and high-tech industries are not an invention of anti-Communist fanatics. Jonathan S. Tobin, National Review, "Don’t Dismiss Communist China’s Critics," 23 July 2019 Luckily, not only did Coinbase and an outside researcher notice the bugs, but Coinbase picked up on the attack before any money could be stolen or the network could be infiltrated. Emily Dreyfuss, WIRED, "Security News This Week: Hackers Used Two Firefox Zero Days to Hit a Crypto Exchange," 22 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infiltrate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of infiltrate

1758, in the meaning defined at transitive sense 1

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Time Traveler for infiltrate

Time Traveler

The first known use of infiltrate was in 1758

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Statistics for infiltrate

Last Updated

10 Dec 2019

Cite this Entry

“Infiltrate.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/infiltration. Accessed 15 December 2019.

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More Definitions for infiltrate

infiltrate

verb
How to pronounce infiltrate (audio) How to pronounce infiltrate (audio)

English Language Learners Definition of infiltrate

: to secretly enter or join (something, such as a group or an organization) in order to get information or do harm
: to cause (someone) to secretly enter or join a group, organization, etc.
technical : to pass into or through (something)

infiltrate

verb
in·​fil·​trate | \ in-ˈfil-ˌtrāt How to pronounce infiltrate (audio) , ˈin-(ˌ) How to pronounce infiltrate (audio) \
infiltrated; infiltrating

Medical Definition of infiltrate

 (Entry 1 of 2)

transitive verb

1 : to cause (as a liquid) to permeate something by penetrating its pores or interstices infiltrate tissue with a local anesthetic
2 : to pass into or through (a substance) by filtering or permeating

intransitive verb

: to enter, permeate, or pass through a substance or area

infiltrate

noun

Medical Definition of infiltrate (Entry 2 of 2)

: something that passes or is caused to pass into or through something by permeating or filtering especially : a substance that passes into the bodily tissues and forms an abnormal accumulation a lung infiltrate

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