2
peppy(adjective, strong, moving, energetic, lively)
2
plodding(adjective, strong, firm, determined, steady)
2
plugging(adjective, strong, keen, firm, lively)
2
ruthless(adjective, resolute)
2
spunky(adjective, resolute, tenacious)
2
stable
2
stiff(adjective, tenacious)
2
stirring(adjective, active)
2
strong-willed(adjective, resolute, tenacious)
2
unbending(adjective, resolute)
2
unchangeable(adjective, resolute)
2
uncompromising(adjective, resolute)
2
unconquerable
2
unshakable
2
unstoppable
1
ambitious
1
ardent
1
ball of fire(expression, adjective, idiom, strong, energetic)
1
bound
1
bound and determined
10 years ago|11k views|share |citing 
APASmart Define. (2016). tireless thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/tireless/thesaurus/synonyms
ChicagoSmart Define. 2016. "tireless thesaurus" https://smartdefine.org/tireless/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, tireless thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/tireless/thesaurus/synonyms>.
MLASmart Define. "tireless thesaurus" 19 February 2016. Web. 24 September 2026. <https://smartdefine.org/tireless/thesaurus/synonyms>