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

Salt water has also infiltrated much of Bahama’s existing water supply. Sanya Mansoor, Time, "Hurricane Dorian Is Gone. But the Bahamas Still Faces a Big Risk From Infectious Disease," 12 Sep. 2019 But her influence had already infiltrated fashionable wardrobes the world over. Vogue, "The Women Designers Who Changed The Way We Dress," 14 Aug. 2019 Amidst this public examination of the work lives of women, a similarly capitalist approach to feminism has infiltrated our personal lives, this one with barely a murmur of recognition. Olivia Goldhill, Quartz, "Feminist capitalism has quietly infiltrated our personal lives," 11 Aug. 2019 Nowadays, television has infiltrated not only diners, coffee shops and pizzerias but also upscale steakhouses, romantic Italian bistros and chic cafes. Bob Brody, WSJ, "If I Wanted a TV Dinner, I’d Stay Home," 20 Sep. 2018 The vice once thought confined mostly to the foolishness of college kids has now apparently infiltrated the lives of more women and more adults age 35 and older. Matthew Martinez, star-telegram, "Is marijuana the ‘social lubricant’ that can cut America’s binge drinking habit? | Fort Worth Star-Telegram," 10 Apr. 2018 The archaeological site was beset by labor strife, work crews had been infiltrated by the powerful Naples Camorra mafia, buildings were crumbling at an alarming rate. Chiara Goia, Smithsonian, "The New Treasures of Pompeii," 21 Aug. 2019 And there’s a big one that every 21st-century business grapples with every day: hackers who relentlessly try to infiltrate computer networks and steal sensitive information. Jonathan Vanian, Fortune, "Meet Chronicle, Alphabet's Latest Moonshot," 19 Feb. 2018 Pastor Albert Rivera, who runs the Agape shelter, said several months ago, a man who pretended to be migrant infiltrated the Agape shelter and began working as a pollero, convincing some young women to try to cross into the United States with him. San Diego Union-Tribune, "Asylum seekers targeted by kidnappers, extortionists and traffickers while waiting in Mexico," 29 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

17 Sep 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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