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

---

Etymology

Origin of counterintelligence

First recorded in 1935–40; counter- + intelligence

Example Sentences

"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

Rodriguez also replaced the head of the presidential guard, who leads the feared counterintelligence unit, and named a new economic czar.

From Barron's • Jan. 12, 2026

“Fidel Castro’s security detail had 10,000 officers and its own counterintelligence unit.”

From The Wall Street Journal • Jan. 6, 2026

Many more questioned his motives; after all, Kalugin was a retired KGB general and had once directed the spy service's counterintelligence operations inside Russia.

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