private detective

a person not on the police force who investigates criminal or illicit activity or searches for missing persons when the police insisted that it was an accident and not murder, she hired a private detective Synonyms dick, gumshoe, hawkshaw, investigator, operative, detective, private eye, private investigator, shamus [slang], sherlock, sleuth, sleuthhoundRelated Words shadow, tail, tracer, tracker; fed, Federal, G-man, narc (or nark) [slang], plainclothesman