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

• 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

Kicking off the development slate are projects Skeleton Coast, a survival thriller to be written and directed by Marshall, and Blackout, an espionage piece to be written and directed by Duffield. —Andreas Wiseman, Deadline, 3 Sep. 2025

This not only puts sensitive defense capabilities at risk of espionage but also directly endangers our service members. —Michael Evanoff, Forbes.com, 2 Sep. 2025

What follows is a crusade of detours, espionage and a paranoid struggle to preserve a vanishing world — and the only home he’s ever known. —Elsa Keslassy, Variety, 31 Aug. 2025

Wu has faced criticism from Republicans over his allegedly close relationship with Chinese officials after photos surfaced of him and consular officials from a Chinese diplomatic post that was raided in 2020 after the federal government accused them of espionage. —Robert Schmad, The Washington Examiner, 27 Aug. 2025

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