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

Explanation

Information and activity that helps to expose or eliminate spying or terrorist threats is counterintelligence. One of the things the CIA is responsible for is counterintelligence. Governments spy on each other, and the action of spying is called intelligence or espionage. When a country works to oppose or uncover spying, it's counterintelligence, or counterespionage. In the United States, both the CIA and the FBI have counterintelligence units. The word has been used since 1940, from counter, "against," and intelligence, from the Latin intelligentia, "power of discerning." The sense of intelligence as "secret information from spies" dates from the 16th century.

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

"We support the use of AI for lawful foreign intelligence and counterintelligence missions," Amodei said.

From BBC • Feb. 26, 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

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

There was a name for what she was doing, a word that had just been invented: counterintelligence.

From "The Woman All Spies Fear" by Amy Butler Greenfield