infiltrate

verb
in·​fil·​trate | \ in-ˈfil-ˌtrāt , ˈin-(ˌ)fil- \
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

Keep scrolling for more

Other Words from infiltrate

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

Synonyms for infiltrate

Synonyms

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

Visit the Thesaurus for More 

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.
See More

Recent Examples on the Web

The initial Bloomberg report alleged that Chinese spies were able to infiltrate critical tech infrastructure belonging to companies like Apple and Amazon by injecting tiny microchips inside Supermicro servers. Makena Kelly, The Verge, "Apple CEO Tim Cook calls for Bloomberg to retract Chinese spy chip report," 19 Oct. 2018 On Thursday morning, Bloomberg published a bombshell story claiming that the Chinese government had used tiny microchips to infiltrate the data centers of Apple and Amazon. Timothy B. Lee, Ars Technica, "Bloomberg stands by Chinese chip story as Apple, Amazon ratchet up denials," 5 Oct. 2018 As New York transplant Michael Halpern continues to infiltrate the ranks of British high fashion, the 29-year-old designer is finding firm footing in glittering eveningwear that channels a decadent retro spirit. Lauren Valenti, Vogue, "This Glamorous Spin on the Glitter Cat-Eye Is a New Party Scene-Stealer," 16 Sep. 2018 This is the second time Hamas allegedly has attempted to infiltrate the Israeli military in this way. Washington Post, BostonGlobe.com, "Israel says Hamas tried to infiltrate its military using dating and sports apps," 3 July 2018 In search of further proof, court papers said, the government also used an informant to infiltrate Mr. Alston’s drug gang. Benjamin Weiser, New York Times, "Days Before Murder Trial, Prosecutors Reveal a Missing Confession," 6 June 2018 Spike Lee's latest tells the true story of two Colorado cops, one black and one Jewish, who team up to infiltrate the local KKK chapter. Todd Mccarthy, The Hollywood Reporter, "'BlacKkKlansman': Film Review | Cannes 2018," 15 May 2018 Still, the pacing is brisk and Raza's perilous journey into the London underworld, infiltrating a gang of Albanian bad guys, draws you in. Taylor Antrim, Vogue, "Three New Crime Shows To Get Hooked on Now," 12 Jan. 2019 Even before the Recession started, news and personal style blogs like Fashionista, Style Bubble, and Bryanboy had begun to infiltrate and democratize the fashion world. Eliza Brooke, Vox, "How the Great Recession influenced a decade of design," 27 Dec. 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.

See More

First Known Use of infiltrate

1758, in the meaning defined at transitive sense 1

Keep scrolling for more

Learn More about infiltrate

Share infiltrate

Statistics for infiltrate

Last Updated

19 Feb 2019

Look-up Popularity

Time Traveler for infiltrate

The first known use of infiltrate was in 1758

See more words from the same year

Keep scrolling for more

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 , ˈin-(ˌ) \
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

Keep scrolling for more

Comments on infiltrate

What made you want to look up infiltrate? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

very full or close together

Get Word of the Day daily email!

Test Your Vocabulary

What did you just call me?! A Quiz

  • rows-of-various-emoji
  • If a member of the audience describes your speech as bombastic, does that person mean it is:
True or False

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ
Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!