| oblique(dishonest, cunning, deceitful, sneaky, underhanded) |
| occult(obscure, strange, unknown, clandestine, underground) |
| privy |
| quiet |
| reserved(adjective, secret, concealment, sneaky, stealthy) |
| reticent(adjective, secret, concealment, sneaky, stealthy) |
| sharp(adjective, mean, smooth, cunning, knowing) |
| slinky(adjective, move) |
| sub-rosa(adjective, dishonest, secret, clandestine, sneaky) |
| under wraps(expression, adjective, dishonest, secret, hidden) |
| underneath(secret, hidden, spy, covert) |
| unknown(obscure, strange, clandestine, underground, curious) |
| untrustworthy(adjective, false, dishonest, cunning, deceitful) |
| abstruse(obscure, strange, unknown, clandestine, underground) |
| alchemistic(strange, unknown, curious, concealed, inexplicable) |
| astrological(strange, unknown, curious, concealed, inexplicable) |
| back-door |
| backdoor(close, obscure, unknown, clandestine, underground) |
| catlike(adjective, move) |
| catty |