11
intelligence(noun, spying)
9
espial(noun, surveillance, spying, snooping)
9
spying
8
reconnaissance(noun, inspection, inquiry, spying)
6
surveillance(noun, intelligence, inspection, spying, snooping)
4
undercover work(noun, expression, idiom, spy, sleeper)
3
watching
3
counterintelligence
2
secret service(noun, spying)
2
bugging(noun, spying)
2
cloak-and-dagger work
2
following(noun, surveillance, snooping)
2
intelligence work
2
looking
2
military intelligence
2
overview(noun, inspection)
2
reconnoiter(noun, inspection)
1
shadowing(noun, spying)
1
tailing(noun, spying)
1
voyeurism(noun, inspection, surveillance, snooping)
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APASmart Define. (2015). espionage thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/espionage/thesaurus/synonyms
ChicagoSmart Define. 2015. "espionage thesaurus" https://smartdefine.org/espionage/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, espionage thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/espionage/thesaurus/synonyms>.
MLASmart Define. "espionage thesaurus" 14 April 2015. Web. 21 September 2026. <https://smartdefine.org/espionage/thesaurus/synonyms>