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 separation is designed to reduce the likelihood that attackers can use vulnerabilities in ancillary hardware to infiltrate the servers.
—
Kelsey Warner, semafor.com, 10 Oct. 2025
In real estate, criminals often infiltrate email accounts, watch a transaction unfold, and strike when closing funds are about to be transferred.
—Collyn Wainwright, Nashville Tennessean, 9 Oct. 2025
Although the use of AI has infiltrated their industry and many others, Diana Haussling, CEO of Hello Products, emphasized the importance of maintaining a human element and understanding different cultures.
—Andrew McGowan, Variety, 9 Oct. 2025
Continue reading … COZY CONNECTIONS – Mamdani hands big check to radical group boasting about infiltrating his campaign.
—FOXNews.com, 8 Oct. 2025
See All Example Sentences for infiltrate
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Kelsey Warner, semafor.com, 10 Oct. 2025
In real estate, criminals often infiltrate email accounts, watch a transaction unfold, and strike when closing funds are about to be transferred.
—Collyn Wainwright, Nashville Tennessean, 9 Oct. 2025
Although the use of AI has infiltrated their industry and many others, Diana Haussling, CEO of Hello Products, emphasized the importance of maintaining a human element and understanding different cultures.
—Andrew McGowan, Variety, 9 Oct. 2025
Continue reading … COZY CONNECTIONS – Mamdani hands big check to radical group boasting about infiltrating his campaign.
—FOXNews.com, 8 Oct. 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 18 Oct. 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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