| recurring(adjective, persistent, continuous, lasting, continuing) |
| relentless(adjective, persistent, obstinate, insistent, dogged) |
| remaining(persistent, lasting) |
| resolute(adjective, firm, determined, usual, regular) |
| solid(familiar, established, long-established) |
| staying(familiar, established, long-established) |
| tenacious(adjective, persistent, obstinate, insistent, dogged) |
| time-honored(familiar, established, long-established) |
| unchangeable(adjective, certain, limited, definite, inflexible) |
| unqualified(adjective, certain, limited, definite, inflexible) |
| well-set(adjective, firm, determined, usual, regular) |
| acknowledged |
| age-long |
| agreed(adjective, certain, determined, usual, regular) |
| anal-retentive(adjective, persistent, obstinate, insistent, dogged) |
| anchored |
| ancient |
| antique |
| appointed(adjective, firm, determined, usual, regular) |
| arranged(adjective, certain, determined, usual, regular) |