steadfastness russian
твёрдость
hardness, solidity, firmness, steadfastness
сто́йкость
firmness, steadfastness, staunchness, stableness, stability, resistance, durability
вы́держанность
firmness, steadfastness, staunchness, self-control, self-command, self-possession, consistency
непоколеби́мость
firmness, steadfastness