| accuser(sneak, informant, squealer) |
| acknowledge(verb, declare, confirm, admit) |
| admit(verb, declare, acknowledge, confirm) |
| affirm(verb, declare, acknowledge, confirm, admit) |
| agent(spy, informer, reporter, gumshoe, investigator) |
| allow(verb, declare, acknowledge, confirm, admit) |
| analyst(agent, spy, informer, reporter, gumshoe) |
| apostate(spy, impostor, renegade, turncoat, hypocrite) |
| assert(verb, declare, acknowledge, confirm, admit) |
| attest(verb, declare, acknowledge, confirm, admit) |
| aver(declare, acknowledge, confirm, admit) |
| avow(declare, acknowledge, confirm, admit) |
| back-stabber(spy, impostor, renegade, turncoat, hypocrite) |
| backseat driver(noun, expression, gossip, nuisance, snoop) |
| backslider(spy, impostor, renegade, turncoat, hypocrite) |
| bear witness against(expression, idiom) |
| bird dog(expression, agent, spy, informer, reporter) |
| blabber |
| blabberer |
| bloodhound(agent, spy, informer, reporter, gumshoe) |