act of God, adamantness, certainty, concentration, constancy, dourness, fate, fatefulness, firmness, firmness of mind, fixedness, flintiness, force majeure, fundamentalism, grimness, hard-bittenness, hard-nosedness, hardness, immobility, immobilization, immovability, immovableness, immutability, implacability, impliability, indefeasibility, inductility, inelasticity, ineluctability, inertia, inescapableness, inevasibleness, inevitability, inevitable accident, inevitableness, inexorability, inextensibility, inextricability, intractability, intransigeance, intransigence, intransigency, intransigentism, irreconcilability, irremovability, irresilience, irresiliency, irrevocability, loyalty, necessity, obduracy, obdurateness, obstinacy, orthodoxy, precisianism, predetermination, purism, puritanism, relentlessness, rigidity, rigidness, rigor, rigorism, rigorousness, settledness, solidity, staunchness, steadfastness, steadiness, steeliness, sternness, stiff temper, stiffness, stubbornness, sureness, toughness, trueness, unalterability, unavoidable casualty, unavoidableness, unbendingness, unchangeability, uncompromisingness, uncontrollability, undeflectability, ungivingness, unlimberness, unmalleability, unmovability, unpliability, unpreventability, unrelentingness, unyieldingness, vis inertiae, vis major