| mysterial(adjective, difficult, mysterious, secret, supernatural) |
| necromantic(strange, supernatural, spiritual, mystical, inexplicable) |
| nonrational(supernatural, spiritual, mystical) |
| odd(unusual, strange, special, rare, unfathomable) |
| off the record(expression, adjective, idiom, intimate, secret) |
| on the QT(expression, idiom, obscure, secret, private) |
| orphic(obscure, complex, deep, mysterious, weird) |
| other-worldly |
| out-of-the-way(obscure, complex, deep, unknown, clandestine) |
| paranormal(adjective, supernatural, spiritual, mystical) |
| preternormal |
| pretersensual |
| psychical |
| quixotic(supernatural, spiritual, mystical) |
| remarkable(adjective, unusual, special, rare) |
| reticent(obscure, deep, unknown, clandestine, underground) |
| retired(obscure, deep, unknown, clandestine, underground) |
| secluded(obscure, unknown, clandestine, underground, undisclosed) |
| secretive(strange, clandestine, underground, undisclosed, inexplicable) |
| shadowy |