espionage

noun

es·​pi·​o·​nage ˈe-spē-ə-ˌnäzh  -ˌnäj 

-nij

Canadian also -ˌnazh;

ˌe-spē-ə-ˈnäzh;

i-ˈspē-ə-nij

: the practice of spying or using spies to obtain information about the plans and activities especially of a foreign government or a competing company

industrial espionage

Synonyms of espionage

• spying

Examples of espionage in a Sentence

He was charged with several counts of espionage.

the acts of espionage on behalf of the Confederacy carried on by Belle Boyd and Rose Greenhow

Recent Examples on the Web

Google similarly detected recent attempts by actors linked to China, Russia, North Korea and Iran to use its Gemini AI model to carry out hacking, disinformation, espionage and criminal operations. — Stephen Collins, The Conversation, 25 Sep. 2026

Kao is widely regarded within Indian intelligence circles as a formative figure in the country’s espionage apparatus, with successive R&AW chiefs having credited his strategic approach. — Naman Ramachandran, Variety, 21 Sep. 2026

Lioness has always been a mess of contradictory political signifiers and anachronistic pop-cultural touchpoints, amounting to a 20th-century-style espionage adventure wrapped in 21st-century military-industrial dystopia. — Andy Andersen, Vulture, 20 Sep. 2026

Five categories of spies are described, and espionage is treated as essential to providing rulers and commanders with the foreknowledge needed to make informed strategic decisions. — Ethan Teekah, Encyclopedia Britannica, 11 Sep. 2026

Word History

Etymology

French espionnage, from Middle French, from espionner to spy, from espion spy, from Old Italian spione, from spia, of Germanic origin; akin to Old High German spehōn to spy — more at spy

First Known Use

1793, in the meaning defined above

Kids Definition

espionage

noun

es·​pi·​o·​nage ˈes-pē-ə-ˌnäzh  -näj 

-ˌnij

: the practice of spying : the use of spies

Legal Definition

espionage

noun

es·​pi·​o·​nage ˈes-pē-ə-ˌnäzh, -ˌnäj, -nij 

: the practice of gathering, transmitting, or losing through gross negligence information relating to the defense of the U.S. with the intent that or with reason to believe that the information will be used to the injury of the U.S. or the advantage of a foreign nation