| inflexible(adjective, tough, firm, determined, resolute) |
| insubordinate(adjective, tough, firm, unreasonable, grim) |
| restive(determined, fixed, stubborn, obstinacy, capricious) |
| uncompromising(adjective, tough, firm, determined, resolute) |
| unruly(adjective, tough, difficult, violent, wild) |
| volitional(adjective, free, deliberate, determined, natural) |
| willing(adjective, free, keen, enthusiastic, deliberate) |
| disobedient(adjective, defiant, mischievous) |
| free(adjective, deliberate, natural, willing, will) |
| heady(adjective, determined, fixed, stubborn, obstinacy) |
| knowing |
| naughty(adjective, bad, misbehaved) |
| optional(adjective, free, deliberate, natural, unreasonable) |
| purposive(adjective, deliberate, determined, careful, thoughtful) |
| spontaneous(adjective, free, deliberate, natural, willing) |
| tenacious(adjective, tough, firm, difficult, resist) |
| uncompelled(adjective, free, deliberate, natural, willing) |
| unrelenting(adjective, determined, resolute, uncompromising, unshakeable) |
| adamantine(adjective, determined, resolute, uncompromising, unshakeable) |
| balky(tough, firm, unreasonable, grim, inflexible) |