1
hard-working
1
heroic
1
high-powered(adjective, strong, moving, energetic, lively)
1
hyper(adjective, determined, persevering)
1
immovable
1
imperturbable(adjective, calm, quiet, gentle, restrained)
1
inalterable
1
indulgent(adjective, calm, quiet, understanding, gentle)
1
inflexible
1
intense
1
intent
1
interminable
1
intrepid
1
jumping(adjective, determined, persevering)
1
kinetic(adjective, strong, moving, energetic, lively)
1
lasting
1
leatherlike
1
leathery
1
lenient(adjective, calm, quiet, understanding, gentle)
1
long-suffering(adjective, calm, quiet, gentle, restrained)
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APASmart Define. (2015). untiring thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/untiring/thesaurus/synonyms
ChicagoSmart Define. 2015. "untiring thesaurus" https://smartdefine.org/untiring/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, untiring thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/untiring/thesaurus/synonyms>.
MLASmart Define. "untiring thesaurus" 14 April 2015. Web. 24 September 2026. <https://smartdefine.org/untiring/thesaurus/synonyms>