Synonyms to plainclothesman

detective, Bow Street runner, FBI, FBI agent, Federal, G-man, MP, Secret Service, Sherlock, Sherlock Holmes, T-man, asker, bailiff, beadle, beagle, bound bailiff, captain, catchpole, catechist, chief of police, commissioner, constable, cop, copper, cross-interrogator, cross-questioner, deputy, deputy sheriff, dick, examiner, eye, fed, federal, flic, gendarme, government man, gumshoe, hawkshaw, hotel detective, house detective, house dick, inquirer, inquiry agent, inquisitionist, inquisitor, inspector, interlocutor, interpellator, interrogator, interrogatrix, interviewer, investigator, lictor, lieutenant, mace-bearer, marshal, mounted policeman, narc, officer, operative, opinion-sampler, patrolman, peace officer, peeper, police captain, police commissioner, police constable, police detective, police inspector, police matron, police officer, police sergeant, policeman, policewoman, poller, pollster, portreeve, private detective, private eye, private investigator, prober, querier, querist, questioner, questionist, quizzer, reeve, revenuer, roundsman, sampler, secret agent, sergeant, ser