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 Judging by the screenshots included alongside the depositions, Twitch security teams appear to have infiltrated the channels and recorded much of the activity. Russell Brandom, The Verge, "Twitch is closing in on its Christchurch trolls," 29 June 2019 Baba Amr would be the last time that the foreign press was able to infiltrate a siege and refute the regime’s propaganda claims. Muhammad Idrees Ahmad, The New York Review of Books, "How Assad Made Truth a Casualty of War," 7 Sep. 2018 Ebola infiltrates its victims’ cells using spiky proteins on the virus’s outer shell, so researchers screened the antibodies for the ones that did the best job of binding to those proteins. Megan Molteni, WIRED, "Ebola Is Now Curable. Here’s How the New Treatments Work," 12 Aug. 2019 Google is similarly racing to fully infiltrate consumers’ lives, making its products and services omnipresent as computing shifts away from phones and laptops and onto other connected devices. David Pierce, WSJ, "Google Unveils New Hardware, Including a Tablet-Laptop Hybrid and a Tabletop Smart Display," 9 Oct. 2018 Building spacefaring equipment on Earth is a dirty business, with fuels, paints, solvents and other toxic materials threatening to infiltrate the natural environment. Robin George Andrews, Scientific American, "Can Spaceflight Save the Planet?," 6 Sep. 2019 Entranced by the genius of author Virginia Woolf (Elizabeth Debicki), Vita sets out to infiltrate her bohemian group of artists and writers. Katie Walsh, San Diego Union-Tribune, "Review: ‘Vita and Virginia’ a swooning and subversive portrait of a literary love affair," 5 Sep. 2019 Their plan is to infiltrate the island and destroy the weaponry that threatens their peaceful existence. Ramona Sentinel, "Flickers: ‘Angel Has Fallen’ and ‘Overcomer’ open Friday," 20 Aug. 2019 Anna Sorokin), a broke Russian immigrant who infiltrated New York City’s elite for years by posing as a wealthy German heiress. David Canfield, EW.com, "The millennial scammer is alive and well in these fascinating new books," 24 July 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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Statistics for infiltrate

Last Updated

29 Oct 2019

Time Traveler for infiltrate

The first known use of infiltrate was in 1758

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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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