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
That group allegedly infiltrated 64 U.S. companies, laundering more than $866,000 through just ten of them.
—
Alonzo Martinez, Forbes.com, 25 Apr. 2025
The disease itself is not deadly, but left untreated, the antibodies can infiltrate different parts of the body like the pancreas, lung or liver.
—David Oliver, USA Today, 23 Apr. 2025
According to prosecutors, undercover police officers managed to infiltrate the defendant’s network by posing as customers.
—Muri Assunção, New York Daily News, 22 Apr. 2025
Comments June and Moira infiltrate Jezebel's disguised as Marthas, but things go south quickly when they're caught by a guardian.
—Matt Cabral, EW.com, 22 Apr. 2025
See All Example Sentences for infiltrate
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Alonzo Martinez, Forbes.com, 25 Apr. 2025
The disease itself is not deadly, but left untreated, the antibodies can infiltrate different parts of the body like the pancreas, lung or liver.
—David Oliver, USA Today, 23 Apr. 2025
According to prosecutors, undercover police officers managed to infiltrate the defendant’s network by posing as customers.
—Muri Assunção, New York Daily News, 22 Apr. 2025
Comments June and Moira infiltrate Jezebel's disguised as Marthas, but things go south quickly when they're caught by a guardian.
—Matt Cabral, EW.com, 22 Apr. 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 4 May. 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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