328 entries under strong topic. ×

4
hardheaded(adjective, hard, determined, unreasonable)
4
immovable(adjective, mean, hard, determined)
4
intense(adjective, clear, complete, severe)
4
lasting(adjective, calm, solid, steady)
4
mulish(adjective, mean, hard, firm)
4
permanent(adjective, calm, solid, steady)
4
red-blooded(adjective, intense, energetic, powerful)
4
set in stone(expression, adjective, idiom, calm, mean)
4
spirited(adjective, energetic, powerful, lively)
4
tireless(adjective, moving, difficult, lively)
4
true(adjective, firm, determined, careful)
4
unalterable(adjective, calm, rough, solid)
4
unchangeable(adjective, calm, solid, substantial)
4
unshakable(adjective, mean, hard, firm)
3
Herculean(adjective, severe, difficult, powerful)
3
Spartan(noble, bold, resolute, spirited)
3
efficient(adjective, complete, intense, exact)
3
forbidding(adjective, hard, severe, firm)
3
forceful(adjective, clear, sound, severe)
3
forcible(adjective, sound, energetic, heavy)
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APASmart Define. (2016). tough thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/tough/thesaurus/synonyms
ChicagoSmart Define. 2016. "tough thesaurus" https://smartdefine.org/tough/thesaurus/synonyms (accessed September 28, 2026).
HarvardSmart Define 2016, tough thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/tough/thesaurus/synonyms>.
MLASmart Define. "tough thesaurus" 30 March 2016. Web. 28 September 2026. <https://smartdefine.org/tough/thesaurus/synonyms>