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
Cyber specialists have long complained that companies treat security as an afterthought, and the result is online services and software that are riddled with bugs, handing hackers a possible way to infiltrate a computer system.
—
Parmy Olson, Twin Cities, 18 Apr. 2026
Director Jon Favreau took the CinemaCon stage to debut the opening 17 minutes of the film, which saw Mando infiltrate a secret meeting of Empire sympathizers and blow up massive AT-AT walkers on a snowy planet.
—Jordan Moreau, Variety, 16 Apr. 2026
But the opening sequence was a rip-roaring cold open in which Mando and Grogu are infiltrating a base to take down an empire loyalist.
—Brian Welk, IndieWire, 16 Apr. 2026
Therefore, it’s taken some time to infiltrate the mainstream, and 2026 is reaching pinnacle ballet flat supremacy.
—Kaitlyn Yarborough, Southern Living, 15 Apr. 2026
See All Example Sentences for infiltrate
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Parmy Olson, Twin Cities, 18 Apr. 2026
Director Jon Favreau took the CinemaCon stage to debut the opening 17 minutes of the film, which saw Mando infiltrate a secret meeting of Empire sympathizers and blow up massive AT-AT walkers on a snowy planet.
—Jordan Moreau, Variety, 16 Apr. 2026
But the opening sequence was a rip-roaring cold open in which Mando and Grogu are infiltrating a base to take down an empire loyalist.
—Brian Welk, IndieWire, 16 Apr. 2026
Therefore, it’s taken some time to infiltrate the mainstream, and 2026 is reaching pinnacle ballet flat supremacy.
—Kaitlyn Yarborough, Southern Living, 15 Apr. 2026
See All Example Sentences for infiltrate
Cite this Entry
“Infiltrate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infiltrate. Accessed 20 Apr. 2026.
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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