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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


counterintelligence British  
/ ˌkaʊntərɪnˈtɛlɪdʒəns /

noun

  1. activities designed to frustrate enemy espionage

  2. intelligence collected about enemy espionage

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Weiner added, “Any list of this nature in Trump’s hands is a counterintelligence nightmare.”

From Slate Jul. 1, 2026

Under the previous Mexican administration, the government conducted strong counterintelligence that tracked U.S. law enforcement efforts across the country, said one person familiar with the operations.

From Los Angeles Times Apr. 22, 2026

Last month, she replaced longtime Defense Minister Vladimir Padrino López with an officer known for his uncompromising stance, former counterintelligence chief Gustavo González.

From The Wall Street Journal Apr. 9, 2026

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

Besides running covert operations, including dirty tricks known as sabotage, Franklin’s work would include gathering intelligence, sending out counterintelligence agents to hunt for moles and British spies, and using propaganda against England.

From "George Washington, Spymaster" by Thomas B. Allen

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