| unflagging(adjective, set, strong, firm, energetic) |
| unswerving(adjective, set, strong, firm, determined) |
| unblinking(adjective, certain, limited, definite, resolute) |
| undaunted(adjective, determined, bold, courage, brave) |
| bold(adjective, courage, resolute) |
| fixed(adjective, strong, flat, firm, certain) |
| inflexible(adjective, strong, flat, firm, harsh) |
| obstinate(adjective, strong, firm, determined, resolution) |
| persevering(adjective, strong, flat, firm, certain) |
| unintimidated(adjective, resolute) |
| unshaken(strong, firm, certain, definite, steadfast) |
| dogged(adjective, strong, firm, harsh, energetic) |
| indefatigable(adjective, set, strong, firm, determined) |
| loyal(adjective, strong, firm, determined, bold) |
| stubborn(adjective, strong, firm, determined, fixed) |
| unbending(adjective, strong, flat, firm, harsh) |
| game(adjective, brave, willing) |
| implacable(adjective, mean, severe, harsh, cruel) |
| inexorable(adjective, mean, severe, harsh, cruel) |
| intrepid(adjective, brave, nervy) |