同義語: invincible, unconquerable, unbeatable, unassailable, impregnable, invulnerable, unsurpassable, unshakeable, indefatigable, unyielding, unbending, stalwart, stout-hearted, lionhearted, strong-willed, strong-minded, staunch, resolute, firm, steadfast, determined, intransigent, inflexible, adamant, unflinching, courageous, brave, valiant, heroic, intrepid, fearless, plucky, mettlesome, gritty, s