infiltrate

verb

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

transitive verb

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

intransitive verb

: to enter, permeate, or pass through a substance or area by filtering or by insinuating gradually
infiltrate noun
infiltration noun
infiltrative
ˈin-(ˌ)fil-ˌtrā-tiv How to pronounce infiltrate (audio)
in-ˈfil-trə-
adjective

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.
Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Even traditional investors have a way to participate with these ETFs, meaning that the language of blockchain is slowly infiltrating even the most resistant population groups. Lisa Loud, Forbes, 5 Nov. 2024 Israel has alleged that the United Nations Relief and Works Agency (UNRWA), which provides support to Palestinian refugees, has been infiltrated by Hamas. David Faris, Newsweek, 4 Nov. 2024 Other familiar faces set to reappear include Gong Yoo as the sharp-suited salesman who finds new recruits for the high-stakes competition, Wi Ha-joon as infiltrating detective Hwang Jun-ho, and Lee Byung-hun as a masked frontman overseeing the game and pulling all the strings. Amarachi Orie, CNN, 1 Nov. 2024 As technology continues to infiltrate and transform mathematics, the question will only become more pressing. Joseph Howlett, Quanta Magazine, 1 Nov. 2024 See all Example Sentences for infiltrate 

Word History

First Known Use

1758, in the meaning defined at transitive sense 4

Time Traveler
The first known use of infiltrate was in 1758

Dictionary Entries Near infiltrate

Cite this Entry

“Infiltrate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infiltrate. Accessed 19 Nov. 2024.

Kids Definition

infiltrate

verb
in·​fil·​trate in-ˈfil-ˌtrāt How to pronounce infiltrate (audio) ˈin-(ˌ)fil- How to pronounce infiltrate (audio)
infiltrated; infiltrating
1
: to pass into or through by filtering
2
: to enter or become established gradually or secretly
infiltration noun

Medical Definition

infiltrate

1 of 2 verb
in·​fil·​trate in-ˈfil-ˌtrāt How to pronounce infiltrate (audio) ˈin-(ˌ) How to pronounce infiltrate (audio)
infiltrated; infiltrating

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

2 of 2 noun
: 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

More from Merriam-Webster on infiltrate

Last Updated: - Updated example sentences
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