1
seeker
1
sifter
1
sleeper(noun, plant, agent, operative, informer)
1
snooper(noun, person)
1
spotter(noun, plant, agent, operative, mole)
1
store detective
1
supervisor
1
surveyor(noun, person, search, first)
1
treasury agent
1
undercover agent(noun, expression, plant, agent, operative)
1
ventilator
1
visitator
1
visitor
0
fed
0
mole(noun, plant, agent, operative, informer)
0
narc
0
plant(noun, agent, operative, informer, mole)
0
spook(noun, plant, agent, operative, informer)
0
CID man
0
Sherlock Holmes(noun, person)
10 years ago|7k views|share |citing 
APASmart Define. (2015). investigator thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/investigator/thesaurus/synonyms
ChicagoSmart Define. 2015. "investigator thesaurus" https://smartdefine.org/investigator/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2015, investigator thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/investigator/thesaurus/synonyms>.
MLASmart Define. "investigator thesaurus" 17 December 2015. Web. 29 September 2026. <https://smartdefine.org/investigator/thesaurus/synonyms>