infiltrate
IN-fil-trayt
/ˈɪnfɪltreɪt/
To secretly enter or join an organization or area, especially in order to spy on it or gain secret information.
Infiltrate implies a gradual, often subtle, penetration, like water seeping through a filter. It's about gaining access without immediate detection, often by blending in.
The story behind the word. The word 'infiltrate' comes from the Latin prefix 'in-' meaning 'into' and 'filtrum,' which means 'felt' or 'filter.' Imagine water slowly seeping through a filter; that's the original image behind 'infiltrate.' It entered English in the 17th century, first referring to liquids passing through porous material, and later, by the 19th century, it gained its more sinister meaning of secretly entering an organization.
Word relationships
- penetrate: More general, can be forceful or non-secretive.
- permeate: Suggests spreading throughout, often passively, like a smell.
- slip into: More informal, implies quiet entry.
- exfiltrate: To extract (someone) from an area, especially a hostile one.
- withdraw: To remove oneself or something from a place.
Word family
- infiltration (noun): The action or process of infiltrating
- infiltrator (noun): A person who infiltrates
Collocations
- infiltrate a group
- infiltrate an organization
- infiltrate enemy lines
- infiltrate a network
- infiltrate the ranks
Example sentences
- "The agent's primary objective was to infiltrate the terrorist cell and gather intelligence from within." The spy managed to infiltrate the enemy's high command.
- "Over time, the rain began to infiltrate the old roof, causing leaks in the attic." Water can infiltrate the soil, reaching the plant roots.
- "The police worked tirelessly to prevent organized crime from attempting to infiltrate local government agencies." Criminal elements attempted to infiltrate legitimate businesses.
Memory hook
Think of 'IN-FILTER-ate' – like water slowly seeping IN through a FILTER, a spy slowly and secretly gets IN. IN-FILTER: seep in.
When not to use
Do not use 'infiltrate' for simply entering a place openly or joining a group as a known member. It specifically implies secret, often deceptive, entry.
Fun facts
- The military use of 'infiltrate' became prominent in the 20th century, describing tactics where small units penetrate enemy lines without being detected.
Related words
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