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

Russia has rejected all accusations of espionage, portraying them as part of anti-Russian hysteria. — Brady Knox, The Washington Examiner, 21 Aug. 2026

The psychological revenge thriller of Season 1 opens up into a globe-trotting espionage thriller taking Reece across the Indian Ocean, Southern and Northern Africa, the Middle East, and Europe. — Denise Petski, Deadline, 20 Aug. 2026

This is the fictional world of the British espionage series Slow Horses (2022– ), based on novelist Mick Herron’s Slough House series and streamed on Apple TV. — Encyclopedia Britannica, 17 Aug. 2026

Germany’s cabinet approved new rules for its spies Wednesday to lift World War II-era restrictions on offensive cyber operations, sabotage, and espionage. — Brendan Ruberry, semafor.com, 12 Aug. 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