| illegible(adjective, incomprehensible, unintelligible, unreadable) |
| indistinct(uncertain, vague, unclear) |
| inexplicit(adjective, obscure, uncertain, vague, unclear) |
| profound |
| questionable(uncertain, doubtful, vague, dubious, unclear) |
| unintelligible(adjective, obscure, difficult, dark, uncertain) |
| unrevealed(adjective, obscure, dark, secret, unknown) |
| absurd(adjective, meaningless) |
| bass |
| classified(obscure, unknown, clandestine, underground, undisclosed) |
| confused |
| enigmatical(adjective, obscure, strange, uncertain, vague) |
| hazy(uncertain, vague, unclear) |
| hermetic(obscure, dark, complex, unknown, hidden) |
| hush-hush(clandestine, underground, undisclosed) |
| inconceivable(adjective, unfathomable, impenetrable, opaque, unintelligible) |
| inconclusive(obscure, uncertain, vague, unclear, indefinite) |
| indeterminate(obscure, uncertain, doubtful, vague, dubious) |
| knotty(adjective, evil, obscure, difficult, sophisticated) |
| nonsensical(adjective, meaningless) |