Synonyms of unflinchingly

2 Syllables
stably, boldly, firmly
3 Syllables
bravely, gallantly, durably, dauntlessly, valiantly, gutsily, headstrongly, doggedly, stolidly, daringly, mulishly, fearlessly, gamely
4 Syllables
unshakeably, heroically, audaciously, valorously, chivalrously, unyieldingly, tenaciously, bullheadedly, intractably, pigheadedly, resistantly, resolvedly
5 Syllables
unrelentingly, obdurately, indomitably, obstinately, unwaveringly, pertinaciously, contumaciously
6 Syllables
opinionatedly