| confidential(adjective, adverb, sensitive, secret, private) |
| off the record(expression, adjective, idiom, adverb, exceptional) |
| private(adjective, secret, confidential) |
| inside(adjective, secret, private, confidential) |
| privileged(sensitive, private, confidential, sub-rosa) |
| secret(adjective, sensitive, private, confidential, sub-rosa) |
| hush-hush(adjective, secret, private, confidential) |
| record |
| unofficial(adjective, adverb, sensitive, secret, private) |
| auricular |
| esoteric |
| in confidence(expression, adverb, sensitive, confidential, eyes-only) |
| on the QT(expression, adjective, idiom, adverb, sensitive) |
| privy(adjective, secret, private, confidential) |
| restricted(private, confidential) |
| sealed |
| arcane(adjective, secret, private, confidential) |
| backdoor(adjective, sensitive, secret, private, confidential) |
| backstairs(sensitive, sub-rosa) |
| between us(expression, adverb, sensitive, confidential, eyes-only) |