| Delphic(solid, dense, unfathomable, impenetrable, impassable) |
| abnormal(adjective, obscure, dark, superior, supernatural) |
| alien(adjective, strange, fantastic, irregular, improper) |
| arcane(adjective, obscure, difficult, solid, strange) |
| bewilder(unintelligibility, misteaching) |
| bewildering(adjective, hard, unclear, tricky, complicated) |
| beyond comprehension |
| beyond understanding |
| bizarre(adjective, strange, fantastic, irregular, improper) |
| cabalistic(adjective, solid, mysterious, dense, hidden) |
| celestial(obscure, dark, superior, mysterious, supernatural) |
| circuitous |
| circumlocutory |
| clear as dishwater(expression, obscure, uncertain, vague, unclear) |
| clouded(adjective, obscure, uncertain, doubtful, dubious) |
| conceal(unintelligibility, misteaching) |
| concealed(adjective, obscure, difficult, dark, superior) |
| confounding(adjective, hard, delicate, complex, tricky) |
| confusing(hard, delicate, uncertain, complex, vague) |
| difficult(adjective, hard, obscure, uncertain, complex) |