| Holmes |
| PI |
| agent(noun, spy, hound, police, informer) |
| analyst(agent, spy, hound, police, informer) |
| beagle |
| bird dog(expression, agent, spy, police, informer) |
| bloodhound(agent, spy, police, informer, reporter) |
| bull(agent, spy, informer, reporter, gumshoe) |
| constable(agent, spy, informer, reporter, gumshoe) |
| cop(agent, spy, informer, reporter, gumshoe) |
| dick(agent, eye, spy, police, informer) |
| eavesdropper(agent, spy, informer, reporter, gumshoe) |
| eye(agent, spy, informer, reporter, gumshoe) |
| fed(agent, spy, police, informer, reporter) |
| fink(agent, spy, informer, reporter, gumshoe) |
| flatfoot(agent, eye, spy, police, informer) |
| gumshoe(agent, eye, spy, hound, police) |
| informer(agent, spy, gumshoe, investigator, dick) |
| inquiry agent |
| inspector |