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
Once Feathers infiltrates their lives, Wallace and his faithful canine companion—along with some friends, like Chief Inspector Mackintosh (Peter Kay)—must then rally to thwart menacing villain’s plans.
—
Travis Bean, Forbes, 11 Jan. 2025
Microbes generally infiltrate natural water by way of—brace yourself—animal poop and pee.
—Erica Sloan, SELF, 10 Jan. 2025
At the same time, some of those who have been forceful advocates of Israel and critics of U.S. assistance to the Lebanese military have often complained that it has been infiltrated by Hezbollah.
—Democrat-Gazette Staff From Wire Reports, arkansasonline.com, 8 Jan. 2025
Part of the series Household Gods, a collection of stories about our relationship to famous people and how celebrities infiltrate our private lives.
—Max Ufberg, hazlitt.net, 4 Jan. 2025
See all Example Sentences for infiltrate 
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Travis Bean, Forbes, 11 Jan. 2025
Microbes generally infiltrate natural water by way of—brace yourself—animal poop and pee.
—Erica Sloan, SELF, 10 Jan. 2025
At the same time, some of those who have been forceful advocates of Israel and critics of U.S. assistance to the Lebanese military have often complained that it has been infiltrated by Hezbollah.
—Democrat-Gazette Staff From Wire Reports, arkansasonline.com, 8 Jan. 2025
Part of the series Household Gods, a collection of stories about our relationship to famous people and how celebrities infiltrate our private lives.
—Max Ufberg, hazlitt.net, 4 Jan. 2025
See all Example Sentences for infiltrate
Dictionary Entries Near infiltrate
Cite this Entry
“Infiltrate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infiltrate. Accessed 18 Jan. 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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