| unvarying(adjective, calm, strong, secure, firm) |
| bearing(noun, verb, adjective, quiet, strength) |
| dateless |
| deathless(adjective, constant, abundant, endless, supreme) |
| diligent(adjective, tenacious) |
| hardy(adjective, strong, sound, tough, fit) |
| incessant(adjective, determined, steady, stable, persistent) |
| infinite(adjective, end, constant, abundant, unrestrained) |
| interminable(adjective, determined, steady, persistent, constant) |
| inveterate(adjective, certain, familiar, limited, definite) |
| lengthy(adjective, great, deep, high, remote) |
| lifelong(adjective, familiar, fixed, established, hardened) |
| old(adjective, continue, familiar, established, hardened) |
| perdurable(adjective, calm, strong, continue, substantial) |
| secure(adjective, calm, strong, sound, tough) |
| staunch(adjective, calm, close, strong, sound) |
| sturdy(adjective, calm, strong, sound, secure) |
| suffering(noun, verb, strength, ability, resolution) |
| surviving(verb, adjective, present, outstanding, living) |
| tireless(adjective, tenacious) |