| mystic(adjective, obscure, solid, dark, superior) |
| difficult(adjective, hard, obscure, strange, uncertain) |
| enigmatical(adjective, hard, solid, strange, dense) |
| exhaustless |
| grandiose(adjective, extravagant, theatrical) |
| illimited |
| inestimable |
| numberless(adjective, constant, abundant, unrestrained, infinite) |
| secret(adjective, obscure, dark, superior, strange) |
| strange(adjective, inexplicable, puzzling, unexplained) |
| termless |
| transcendental(obscure, dark, strange, mysterious, supernatural) |
| unclear(adjective, hard, obscure, difficult, uncertain) |
| undiscoverable(adjective, hidden, incomprehensible, enigmatic, unintelligibility) |
| unending(adjective, complete, deep, constant, abundant) |
| unexplainable(adjective, obscure, strange, odd, mysterious) |
| without end(expression, idiom, constant, abundant, unrestrained) |
| without limit(expression, idiom, infinity) |
| without measure(expression, idiom, infinity) |
| without number(expression, idiom, infinity) |