| traitor(noun, person, opposition, trust, agent) |
| informer(noun, opposition, source, agent, villain) |
| double-crosser(noun, person, trust, source, spy) |
| squealer(noun, source, spy, grass, sneak) |
| turncoat(noun, source, spy, sneak, informer) |
| snitch(noun, source, spy, grass, sneak) |
| nark(noun, source, grass, sneak, decoy) |
| spy(noun, opposition, source, agent, villain) |
| Benedict Arnold(noun, expression, spy, informer) |
| canary(noun, source, grass, sneak, informer) |
| deceiver(noun, source, talent, sneak, informer) |
| fink(noun, source, spy, grass, sneak) |
| stool pigeon(noun, expression, source, sneak, informer) |
| stoolie(noun, source, grass, sneak, informer) |
| narc(noun, source, grass, sneak, decoy) |
| snitcher(noun, source, spy, grass, sneak) |
| weasel(noun, source, grass, sneak, decoy) |
| tattletale(source, spy, grass, sneak, informer) |
| whistle-blower(source, spy, grass, sneak, informer) |
| accuser(noun, source, sneak, informant) |