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Synonyms

espionage

American  
[es-pee-uh-nahzh, -nij, es-pee-uh-nahzh] / ˈɛs pi əˌnɑʒ, -nɪdʒ, ˌɛs pi əˈnɑʒ /

noun

  1. the act or practice of spying.

  2. the use of spies by a government to discover the military and political secrets of other nations.

  3. the use of spies by a corporation or the like to acquire the plans, technical knowledge, etc., of a competitor.

    industrial espionage.


espionage British  
/ ˌɛspɪəˈnɑːʒ, ˈɛspɪəˌnɑːʒ, ˈɛspɪənɪdʒ /

noun

  1. the systematic use of spies to obtain secret information, esp by governments to discover military or political secrets

  2. the act or practice of spying

"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

Other Word Forms

Etymology

Origin of espionage

First recorded in 1785–95; from French espionnage, Middle French espionage, from espionn(er) “to spy” (derivative of espion “a spy,” from Italian spione, from Germanic ) + -age -age; see espy

Explanation

It's no secret: espionage is the act of organized spying, usually with the goal of uncovering sensitive military or political information. If the government has relocated you to a foreign country, made you change your name, given you a fake mustache to wear, and instructed you to hide in a closet at the presidential palace and report back weekly on what you overhear, then you are engaging in espionage. This noun is similar to snooping, but generally applies to much more serious situations, like when countries or businesses spy on each other to try to obtain top secret information.

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Vocabulary lists containing espionage

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.

"Espionage is a security issue for Austria," Meinl-Reisinger said in a statement sent to the BBC.

From BBC • May 4, 2026

Espionage accusations between the two countries date back far further than the Ukraine offensive.

From Barron's • Jan. 15, 2026

Assange agreed to plead guilty to one count of violating the Espionage Act and the government agreed to sentence him to time served.

From The Wall Street Journal • Jan. 8, 2026

Espionage allegations have been levelled against several high-ranking Taiwan officials in recent years, including an ex-air force colonel who in 2023 was jailed for 20 years for running a military spy ring for China.

From BBC • Sep. 26, 2025

The paper would be prosecuted under the Espionage Act, warned Louis Loeb, one of the firm’s partners.

From "Most Dangerous: Daniel Ellsberg and the Secret History of the Vietnam War" by Steve Sheinkin