Definition of infiltrate
1 : to cause (something, such as a liquid) to permeate something by penetrating its pores or interstices
2 : to pass into or through (a substance) by filtering or permeating
3 : to pass (troops) singly or in small groups through gaps in the enemy line
4 : to enter or become established in gradually or unobtrusively usually for subversive purposes the intelligence staff had been infiltrated by spies
: to enter, permeate, or pass through a substance or area by filtering or by insinuating gradually
infiltrationplay \ˌin-(ˌ)fil-ˈtrā-shən\ noun
infiltrativeplay \ˈin-(ˌ)fil-ˌtrā-tiv, in-ˈfil-trə-\ adjective
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 of infiltrate from the Web
Wimbledon, one of the most prominent tennis tournaments in the world, was faced with a predicament today: A massive swarm of flying ants infiltrated the courts, wreaking havoc on the players, umpires, and spectators.
Many of the deaths in recent years have been caused by heroin and illicit fentanyl - a powerful substance that has infiltrated the drug supply and caused a spike in overdoses.
Now, however, athletic style has infiltrated practically every facet of our lives.
As Bloomberg recently reported, Russian hackers infiltrated voter databases and software systems in 39 U.S. states as part of a wide-ranging effort to disrupt and influence the 2016 presidential election.
Allende is a town so thoroughly infiltrated by the powerful cartel, there was little leadership or resistance to the violence.
After that, cats infiltrated the rest of Europe, Africa, and Asia.
Both drugs reduced graft-infiltrating immune cells [a marker for rejection].
Several assailants infiltrated the Majlis, Iran’s Parliament, and opened fire before security forces neutralized them.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infiltrate'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use of infiltrate
INFILTRATE Defined for English Language Learners
Definition of infiltrate for English Language Learners
: to secretly enter or join (something, such as a group or an organization) in order to get information or do harm
: to cause (someone) to secretly enter or join a group, organization, etc.
: to pass into or through (something)
Medical Definition of infiltrate
transitive verb: 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
intransitive verb: to enter, permeate, or pass through a substance or area
Medical Definition of infiltrate
: 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
Seen and Heard
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