| Main Entry: | |
| Part of Speech: | adjective |
| Definition: | complicated |
| Synonyms: | complex, intricate, involved, perplexing, tangled |
| Main Entry: | insoluble |
| Part of Speech: | adjective |
| Definition: | mysterious, unable to be solved or answered |
| Synonyms: | baffling, difficult, impenetrable, indecipherable, inexplicable, inextricable, irresolvable, mystifying, obscure, unaccountable, unconcluded, unfathomable, unresolved, unsolvable, unsolved |
| Antonyms: | explainable, explicable, obvious, open, solvable |
| Main Entry: | unsolvable |
| Part of Speech: | adjective |
| Definition: | not easily solved |
| Synonyms: | inexplicable, inextricable, inscrutable, insoluble, unexcogitable |
| Antonyms: | solvable |