| willful(adjective, tough, firm, resist, determined) |
| hardheaded(adjective, strong, hard, tough, resist) |
| adamantine(adjective, strong, hard, tough, firm) |
| implacable(adjective, mean, strong, hard, tough) |
| pertinacious(adjective, tough, firm, resist, determined) |
| self-willed(adjective, tough, firm, determined, resolute) |
| determined(adjective, firm, deliberate, usual, regular) |
| grim(adjective, strong, hard, tough, severe) |
| immovable(adjective, mean, strong, hard, tough) |
| intolerant(adjective, severe) |
| intractable(adjective, tough, firm, stupid, unreasonable) |
| tenacious(adjective, tough, firm, resist, unreasonable) |
| hidebound(adjective, severe) |
| narrow-minded |
| puritanical(adjective, severe) |
| stern(adjective, severe, determined, serious, resolute) |
| bigoted |
| firm(adjective, mean, strong, hard, tough) |
| hard(adjective, mean, strong, tough, harsh) |
| hard-nosed(adjective, mean, strong, hard, tough) |