| tough(adjective, reliable, steadfast, loyal, faithful) |
| tried and true(expression, adjective, idiom, firm, honest) |
| true-hearted(good, strong, solid, steady, consistent) |
| unbending(adjective, resolute, persistent, dedicated, unwavering) |
| unchanging |
| unequivocal(good, strong, solid, steady, consistent) |
| unfaltering(adjective, resolute, persistent, reliable, steadfast) |
| unflinching(adjective, resolute, persistent, dedicated, unwavering) |
| unimpeachable(strong, solid, steady, consistent, steadfast) |
| unlimited |
| unmovable(adjective, resolute, persistent, dedicated, unwavering) |
| unqualified(adjective, resolute, persistent, dedicated, unwavering) |
| unquestioning(adjective, intense, resolute, persistent, dedicated) |
| unrelenting |
| unshakable |
| unshaken(adjective, trustworthy, faithful) |
| unyielding(adjective, resolute, persistent, dedicated, unwavering) |
| wholehearted(adjective, intense, resolute, persistent, dedicated) |
| hard-core(adjective, firm, honest, ardent, upright) |