| mystic(obscure, unknown, clandestine, underground, undisclosed) |
| mystical(obscure, unknown, clandestine, underground, undisclosed) |
| not well-known |
| occult(obscure, unknown, clandestine, underground, undisclosed) |
| off beaten track(expression, unusual, detached, remote, lonely) |
| off the beaten path(adjective, path) |
| old(discharged, superannuated, emeritus) |
| on the QT(expression, idiom, obscure, unknown, clandestine) |
| otiose(discharged, superannuated, emeritus) |
| pacific(adjective, shy, stable, peaceful, tranquil) |
| pensioned off(expression, discharged, superannuated, emeritus) |
| philosophy(adjective, quiet, lonely, neglected, syllogistics) |
| placid(adjective, shy, stable, peaceful, tranquil) |
| privy |
| random(unusual, detached, remote, lonely, inaccessible) |
| rarely visited(expression, idiom) |
| ratiocination(adjective, quiet, lonely, neglected) |
| rationale(adjective, quiet, isolated, lonely, neglected) |
| recondite(obscure, unknown, clandestine, underground, undisclosed) |
| rejected |