| Rating | Solver | Clue |
|---|---|---|
| ONEROUS | Arduous | |
| HARD | Arduous | |
| STRENUOUS | Arduous | |
| ODYSSEY | Arduous journey | |
| SLOGS | Arduous journeys | |
| ODYSSEYS | Arduous journeys | |
| DUO | Arduous little pair | |
| TREK | Arduous journey on foot | |
| ARDUOUSNESS | The quality of being arduous; difficulty of execution. | |
| ARDUOUSLY | In an arduous manner; with difficulty or laboriousness. | |
| DIFFICULT | Hard to do or to make; beset with difficulty; attended with labor, trouble, or pains; not easy; arduous. | |
| ARDUOUS | Attended with great labor, like the ascending of acclivities; difficult; laborious; as, an arduous employment, task, or enterprise. | |
| -OUS | ..., having, possessing the qualities of, like; as in gracious, abounding in grace; arduous, full of ardor; bulbous, having bulbs, bulblike; riotou... | |
| ENTERPRISE | ...be performed; a work projected which involves activity, courage, energy, and the like; a bold, arduous, or hazardous attempt; an undertaking; ... | |