| astute(adjective, hard, sound, sharp, practical) |
| bovine(adjective, determined, resolute, obstinate, uncompromising) |
| brass-bound(adjective, determined, resolute, obstinate, uncompromising) |
| bull-headed(adjective, determined, resolute, obstinate, uncompromising) |
| firm(adjective, strong, hard, tough, determined) |
| grim(adjective, strong, hard, tough, determined) |
| hardened(adjective, determined, resolute, uncompromising, unshakeable) |
| implacable(adjective, strong, hard, tough, firm) |
| objective(adjective, hard, sound, excite, rational) |
| pig-headed(adjective, determined, resolute, obstinate, uncompromising) |
| prosaic(adjective, hard, sound, excite, rational) |
| shrewd(adjective, hard, sound, sharp, practical) |
| calculating |
| down to earth(expression, idiom) |
| fixed(tough, firm, determined, resolute, obstinate) |
| harsh(adjective, strong, hard, tough, severe) |
| inconvincible(adjective, determined, resolute, uncompromising, unshakeable) |
| insistent(adjective, determined, resolute, obstinate, uncompromising) |
| ossified(adjective, determined, resolute, uncompromising, unshakeable) |
| persevering(tough, firm, determined, unreasonable, grim) |