indomitable
Slowly, indomitably, she fought back.
Her children are indomitably charming.
He has been indomitably trying to learn English.
SMART Vocabulary: related words and phrases Strong-willed
adamancy
adamant
adamantine
adamantly
aggressive
grittily
gutsily
gutsy
gutty
hard-boiled
pertinaciously
pigheaded
pigheadedly
purposeful
purposefully
ultra-serious
unbending
unbroken
undaunted
unmovable
You can also find related words, phrases, and synonyms in the topics:
Brave and courageous