| impenetrable(adjective, difficult) |
| labyrinthian |
| meandering(adjective, hard, difficult, tricky, complicated) |
| mysterious(adjective, hard, obscure, delicate, tricky) |
| preoccupation(noun, worry, passion, desire, anxiety) |
| repression(noun, problem, obsession) |
| set with thorns(expression, idiom) |
| strenuous(adjective, difficult) |
| unfathomable(adjective, hard, obscure, difficult, tricky) |
| whole(noun, entity, business, order, total) |
| winding(adjective, difficult) |
| can of worms(expression, adjective, idiom, hard, fancy) |
| Daedalean(adjective, hard, fancy, difficult, involved) |
| abstract(adjective, hard, obscure, delicate, intellectual) |
| arcane |
| character(noun, nature, quality, spirit, temperament) |
| complication(noun, network) |
| compulsion(noun, passion, desire, thing, enthusiasm) |
| confounded(adjective, complicated) |
| cross-cultural(adjective, union, unity, amalgamation, joining) |