| robust(adjective, strong, prevailing, influential, commanding) |
| taxing(adjective, hard, tough, severe, rough) |
| unbelievable |
| wearing(adjective, tough, rough, difficult, heavy) |
| wearisome(adjective, tough, severe, difficult, awkward) |
| wearying(adjective, tough, rough, difficult, heavy) |
| wicked(adjective, bad, nasty, delicate, unpleasant) |
| abstruse(hard, intense, heavy, fierce, tricky) |
| ambitious(adjective, ability, effort) |
| authoritative(adjective, prevailing, influential, commanding) |
| backbreaking(adjective, hard, tough, severe, rough) |
| bothersome(adjective, tough, severe, difficult, awkward) |
| brawny(adjective, strong) |
| brutal |
| cantankerous(adjective, hard, evil, rough, nasty) |
| compelling(prevailing, influential, commanding) |
| critical(adjective, dangerous) |
| cumbersome(adjective, difficult) |
| deadly(adjective, dangerous) |
| delicate(bad, hard, difficult, heavy, complex) |