| dour(adjective, strong-willed, headstrong, businesslike) |
| insistent(adjective, persistent, stubborn, indomitable) |
| irremissive(adjective, persistent, stubborn, indomitable) |
| obdurate(adjective, strong-willed, headstrong, businesslike) |
| pretentious(adjective, ambitious, aspirational, high flying) |
| rebellious(adjective, persistent, stubborn, indomitable) |
| resolute(adjective, persistent, stubborn, indomitable) |
| restive(adjective, strong-willed, headstrong, businesslike) |
| unbending(adjective, tough, inflexible, adamant, businesslike) |
| hard(adjective, persistent, stubborn, indomitable) |
| adamantine(adjective, tough, inflexible, adamant, businesslike) |
| stanch(adjective, persistent, stubborn, indomitable) |
| staunch(adjective, persistent, stubborn, indomitable) |
| steadfast(adjective, persistent, stubborn, indomitable) |
| steady(adjective, persistent, stubborn, indomitable) |
| stout(adjective, persistent, stubborn, indomitable) |
| sturdy(adjective, persistent, stubborn, indomitable) |
| tenacious(adjective, persistent, stubborn, indomitable) |
| tireless(adjective, persistent, stubborn, indomitable) |
| unchangeable(adjective, strong-willed, headstrong, businesslike) |