infiltrate
verb
in·fil·trate
ˈin-(ˌ)fil-ˌtrāt 
in-ˈfil-
in-ˈfil-
infiltrated; infiltrating
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
: to enter, permeate, or pass through a substance or area by filtering or by insinuating gradually
infiltrate
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.
Recent Examples on the Web
But when the Israeli secret service recruits Uri for a dangerous mission in Germany, he is forced to return home and infiltrate a cell of SS veterans with the aim of locating the Nazi war criminal, Mengele.
—
Max Goldbart, Deadline, 23 Mar. 2025
With time running out and no viable diplomatic solutions, authorities send in Snake to infiltrate the island and rescue the President in exchange for his own freedom.
—Travis Bean, Forbes, 22 Mar. 2025
In what many critics called a return to form for Spike, his 2018 crime drama BlacKkKlansman saw John David Washington as a detective trying to infiltrate and expose a local Ku Klux Klan chapter.
—Brendan Le, People.com, 20 Mar. 2025
Inspired by one of the most remarkable criminal investigations ever conducted, the six-part drama follows a group of British Customs employees sent undercover to infiltrate some of the country’s most dangerous criminal drug gangs.
—Lily Ford, The Hollywood Reporter, 19 Mar. 2025
See All Example Sentences for infiltrate
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Max Goldbart, Deadline, 23 Mar. 2025
With time running out and no viable diplomatic solutions, authorities send in Snake to infiltrate the island and rescue the President in exchange for his own freedom.
—Travis Bean, Forbes, 22 Mar. 2025
In what many critics called a return to form for Spike, his 2018 crime drama BlacKkKlansman saw John David Washington as a detective trying to infiltrate and expose a local Ku Klux Klan chapter.
—Brendan Le, People.com, 20 Mar. 2025
Inspired by one of the most remarkable criminal investigations ever conducted, the six-part drama follows a group of British Customs employees sent undercover to infiltrate some of the country’s most dangerous criminal drug gangs.
—Lily Ford, The Hollywood Reporter, 19 Mar. 2025
See All Example Sentences for infiltrate
Cite this Entry
“Infiltrate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infiltrate. Accessed 29 Mar. 2025.
Copy CitationKids Definition
infiltrate
verb
in·fil·trate
in-ˈfil-ˌtrāt
ˈin-(ˌ)fil-
ˈin-(ˌ)fil-
infiltrated; infiltrating
1
: to pass into or through by filtering
2
: to enter or become established gradually or secretly
Medical Definition
infiltrate
1 of 2 verb
in·fil·trate
in-ˈfil-ˌtrāt
ˈin-(ˌ)
ˈin-(ˌ)
infiltrated; infiltrating
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
: 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
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