dedication, attachment, piety, faith, allegiance, troth, loyalty, continue, commitment, devotedness, fealty, obligation, adhesion, fastness, fidelity.
perseverance (part of speech: noun)
- staying power,
stability (part of speech: noun)
tenacity (part of speech: noun)
resolution (part of speech: noun)
The bell rings a third time, long and insistently, but the youngster, with a steadfastness
worthy of the boy who stood on the burning deck, still keeps his place.
- "The Book of Business Etiquette", Nella Henney.
Bravely she answered, bracing soul and mind and body to steadfastness.
- "Flamsted quarries", Mary E. Waller.
Don't think I'm doubting your steadfastness,
old man, I believe in it.
- "The Altar Steps", Compton MacKenzie.