| stubborn(adjective, obstinate, determined, characteristic, quality) |
| obstinate(adjective, mean, strong, hard, tough) |
| obdurate(adjective, strong, hard, tough, firm) |
| inflexible(adjective, mean, strong, hard, tough) |
| dogged(adjective, mean, strong, hard, tough) |
| headstrong(adjective, tough, firm, resist, determined) |
| pigheaded(adjective, mean, hard, tough, difficult) |
| unyielding(adjective, mean, strong, hard, tough) |
| hardheaded(adjective, strong, hard, tough, firm) |
| adamant(adjective, mean, strong, hard, tough) |
| pertinacious(adjective, strong, tough, firm, difficult) |
| tenacious(adjective, strong, tough, firm, resist) |
| bullheaded(adjective, strong, hard, tough, difficult) |
| uncompromising(adjective, mean, hard, deliberate, determined) |
| firm(adjective, mean, strong, hard, tough) |
| immovable(adjective, mean, strong, hard, tough) |
| intractable(adjective, tough, firm, difficult, indifferent) |
| perverse(adjective, mean, hard, tough, difficult) |
| refractory(adjective, tough, firm, difficult, determined) |
| rigid(adjective, mean, strong, hard, tough) |