102 entries under persistent topic. ×

1
iron(verb, adjective, strong, tough, firm)
1
iron-fisted(adjective, constant, pitiless, unyielding)
1
merciless(adjective, harsh, cruel, determined, fierce)
1
mortal(adjective, harsh, cruel, determined, fierce)
1
never-failing(adjective, set, strong, flat, firm)
1
perpetual(adjective, determined, steady, resolute)
1
pitiless(adjective, harsh, cruel, determined, fierce)
1
remorseless(adjective, harsh, cruel, determined, fierce)
1
rigorous(adjective, harsh, cruel, determined, fierce)
1
ruthless(adjective, harsh, cruel, determined, fierce)
1
solid(adjective, close, strong, tough, firm)
1
stiff(adjective, firm, harsh, cruel, determined)
1
stiff-necked(adjective, set, firm, sure)
1
stop at nothing(expression, adjective, idiom, harsh, cruel)
1
strict(adjective, strong, flat, harsh, certain)
1
stringent(adjective, harsh, cruel, determined, fierce)
1
strong(adjective, close, tough, flat, firm)
1
unabated(adjective, constant, pitiless, unyielding)
1
unappeasable(adjective, harsh, cruel, determined, fierce)
1
unbroken(adjective, constant, pitiless, unyielding)
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APASmart Define. (2016). bound thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/bound/thesaurus/synonyms
ChicagoSmart Define. 2016. "bound thesaurus" https://smartdefine.org/bound/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, bound thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/bound/thesaurus/synonyms>.
MLASmart Define. "bound thesaurus" 26 February 2016. Web. 21 September 2026. <https://smartdefine.org/bound/thesaurus/synonyms>