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

Synonyms for infiltrate

Synonyms

insinuate, slip, sneak, wind, work in, worm, wriggle

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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

As casting diversity continues to infiltrate and disrupt the runways, the new rule for Fashion Month is anything goes. Christian Allaire, Vogue, "How This Teenage Hacker Became an Unlikely Star of London Fashion Week," 16 Sep. 2018 Mistress Genevieve confesses that the occasional political headline can infiltrate her line of work, and those able to afford her standard rate of $400 an hour in a deeply red state like Louisiana aren't generally members of the #Resistance. Andrew Paul, GQ, "What Golden Shower Practitioners Think About a Certain Rumored Pee Tape," 24 Apr. 2018 Chief among these is Praxagora, originally the heroine of Aristophanes's Ecclesiazusæ (women disguise themselves as men, infiltrate the Athenian city council, and rearrange things). Tony Adler, Chicago Reader, "In four hours, the Aristophanesathon never cracks the whimsy barrier," 18 Apr. 2018 In extreme cases like these, the particle streams infiltrate the magnetosphere, blending with Earth’s atmosphere and coating forests and ice sheets in radionuclides for scientists to contemplate thousands of years later. Jill Kiedaisch, Popular Mechanics, "Evidence of a Monstrous, Ancient Solar Storm Found Hidden in Greenland's Ice," 14 Mar. 2019 Chinese spies have infiltrated the supply chain for servers used by nearly 30 US companies, including government contractors, Apple, and Amazon, according to an explosive report from Bloomberg Businessweek. James Vincent, The Verge, "Chinese spies reportedly inserted microchips into servers used by Apple, Amazon, and others," 4 Oct. 2018 As the truck passed deeper inside the 2.5-mile tube, Mr. Cuomo pointed out for the camera areas where water from the river just 20 feet above had infiltrated the pockmarked concrete roof, dripping from the ceiling and corroding pipes and rebar. Paul Berger, WSJ, "Cuomo Digs In on Aging Train Tunnel to Penn Station, Telling Trump to Fork Over Funding," 18 Oct. 2018 The assault on Ghazni, the capital of Ghazni province, was a major show of force by the Taliban, who had infiltrated deep into the city and attacked from several directions. Fox News, "The Latest: Scores killed in battle for key Afghan city," 13 Aug. 2018 Israeli officials have not issued any response to reports of the strike, but its warplanes hit the same facility in February, after Israel said an Iranian drone had infiltrated its airspace. CNN, "US allies warn of action on suspected Syria chemical attack," 10 Apr. 2018

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

16 Apr 2019

Look-up Popularity

Time Traveler for infiltrate

The first known use of infiltrate was in 1758

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More Definitions for infiltrate

infiltrate

verb

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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