Synonyms and related words :
abidingness, body, ceaselessness, changelessness, coeternity, cohesiveness, concreteness, constancy, continualness, continuance, density, durableness, duration, endlessness, endurance, eternalness, eternity, ever-duringness, everlastingness, everness, firmness, fixedness, foreverness, frozenness, hardening, hardiness, hardness, immobility, immovability, immovableness, immutability, incessancy, indestructibility, infinite duration, infinity, infrangibility, interminability, invariability, invariableness, inveteracy, lastingness, leatherlikeness, long standing, mass, materiality, never-endingness, palpability, perdurability, perenniality, perennialness, permanence, permanency, perpetualness, perpetuity, persistence, persistency, ponderability, quiescence, resistance, rigidity, ropiness, sempiternity, solidity, soundness, stability, stamina, standing, stasis, steadfastness, steadiness, stiffness, stoutness, strength, stringiness, stubbornness, sturdiness, substance, substantiality, substantialness, tangibility, tenacity, timelessness, torpor, toughness, unbreakability, unbreakableness, unceasingness, unchangeability, unchangingness, viscidity, vitality