tenaciously Synonyms

doggedly with heavy hand mulishly deucedly severely adamantly tuggingly toughly tightly strongly strictly stoutly obdurately obstinately stubbornly unwaveringly stolidly single-mindedly unyieldingly pertinaciously perseveringly indomitably faithfully decisively dauntlessly stiffly steadily firmly firm FAST diligently determinedly decidedly courageously constantly bravely boldly fixedly hard indefatigably steadfastly staunchly solidly securely rigidly resolutely persistently intently insistently inflexibly