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counterintelligence

American  
[kaun-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:

The constant pressure from Russian counterintelligence was the primary source of such uncertainty, she recalls.

From BBC ● Oct. 22, 2026

“If I’m paying for your wedding, at some point, you’re going to owe me something,” said Frank Montoya Jr., a retired career FBI official who held senior counterintelligence roles.

From Salon ● Sep. 14, 2026

“Drones are just more effective and cost less,” said Kovalskiy, who is part of a military counterintelligence division of the Security Service of Ukraine, or SBU.

From The Wall Street Journal ● May 14, 2026

The number of FBI employees working in counterterrorism and counterintelligence continues to fall.

From Slate ● Apr. 21, 2026

On July 20, 1993, the FBI summoned Ames to a meeting at FBI headquarters, supposedly related to his counterintelligence work.

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

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