counterintelligence

American  

[koun-ter-in-tel-i-juhns] / ˌkaʊn tər ɪnˈtɛl ɪ dʒəns /

noun

1. the activity of an intelligence service employed in thwarting the efforts of an enemy's intelligence agents to gather information or commit sabotage. CI

2. an organization engaged in counterintelligence. CI

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counterintelligence British  

/ ˌkaʊntərɪnˈtɛlɪdʒəns /

noun

1. activities designed to frustrate enemy espionage

2. intelligence collected about enemy espionage

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Etymology

Origin of counterintelligence

First recorded in 1935–40; counter- + intelligence

Example Sentences

It calls for a mandatory registration system for foreign agents -- such as individuals and corporations lobbying within Japan on behalf of other governments -- as part of counterintelligence measures.

From Barron's • Feb. 27, 2026

The verdict marked the Justice Department’s first conviction on AI-related economic espionage charges, according to a statement from Roman Rozhavsky, assistant director of the FBI’s counterintelligence and espionage division.

From Los Angeles Times • Jan. 30, 2026

He married his first wife, fellow CIA agent Nancy Segebarth, in 1969, before being sent to Turkey as a counterintelligence officer to recruit foreign agents.

From BBC • Jan. 6, 2026

Ahead of Friday’s release, CNN reported that the Justice Department was racing to redact thousands of pages of documents, with insiders describing the redaction process as a top priority for counterintelligence specialists.

From Salon • Dec. 19, 2025

Following HERO'S arrest, they had stopped recruiting Soviet informers under orders from James Jesus Angleton, the secretive and paranoid CIA chief of counterintelligence.

From "Spies: The Secret Showdown Between America and Russia" by Marc Favreau