infiltration
C1Formal, Academic, Technical
Definition
Meaning
The act of secretly or gradually entering or joining a group, place, or system, especially for military, espionage, or harmful purposes.
The process of a substance (like water) passing gradually into or through something; also refers to the unwanted introduction of people or ideas into an organization.
Linguistics
Semantic Notes
Primarily a process noun. While often negative (espionage, sabotage), it can be neutral in scientific contexts (e.g., water infiltration).
Dialectal Variation
British vs American Usage
Differences
No significant difference in core meaning or spelling. The word is used identically in both varieties.
Connotations
Equally strong connotations of secrecy and potential threat in both contexts.
Frequency
Slightly more frequent in US media due to common use in political and espionage reporting, but this is marginal.
Vocabulary
Collocations
Grammar
Valency Patterns
infiltration of [PLACE/GROUP] (by [AGENT])infiltration into [PLACE/GROUP]Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “A fifth column”
Usage
Context Usage
Business
Refers to competitors gaining access to confidential information or market share.
Academic
Used in history (espionage), political science (subversion), geology/engineering (fluid flow).
Everyday
Rare. Might be used for jokes about someone joining a group (e.g., 'My infiltration of the book club is complete').
Technical
Key term in military science, counter-intelligence, hydrology, and materials science.
Examples
By Part of Speech
verb
British English
- The agency managed to infiltrate the criminal network.
- Rainwater had infiltrated the old brickwork.
American English
- Agents worked to infiltrate the extremist group.
- The dye infiltrated the fabric fibers completely.
adjective
British English
- The infiltration attempt was discovered.
- They studied the soil's infiltration capacity.
American English
- An infiltration operation was underway.
- The infiltration rate of the pavement was tested.
Examples
By CEFR Level
- The police were worried about infiltration by gang members.
- Water infiltration caused damage to the basement walls.
- The security services detected a foreign infiltration of the research institute.
- The report warned of ideological infiltration into online communities.
- Counter-intelligence focuses on preventing the infiltration of sensitive government departments.
- The study measured the rate of chemical infiltration through different types of membrane.
Learning
Memory Aids
Mnemonic
Think of a FILTER: infiltration is like something passing THROUGH a FILTER secretly.
Conceptual Metaphor
IDEAS/WATER ARE AGENTS THAT SECRETLY FLOW INTO A CONTAINER.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'инфильтрация' in purely medical context (medical infiltration).
- Avoid over-literal translation when used for people ('проникновение' is often better).
Common Mistakes
- Using 'infiltration' for a single, open entry (use 'entry').
- Confusing 'infiltration' (process) with 'infiltrator' (person).
Practice
Quiz
In a geological context, 'infiltration' most likely refers to:
FAQ
Frequently Asked Questions
No, in technical fields like hydrology or engineering, it is a neutral term describing a physical process.
'Infiltration' strongly implies secrecy, slowness, and often an unwanted or hostile agent. 'Penetration' can be sudden, forceful, and more general.
The verb form is 'to infiltrate'. 'Infiltration' is the noun describing the process or result.
Yes, such a person is called an 'infiltrator'.