108 entries under stiff topic. ×

20
stout(adjective, strong, sound, tough, strain)
19
fast(adjective, strong, secure, tough, strain)
19
robust(adjective, strong, hard, sound, tough)
19
substantial(adjective, strong, hard, sound, tough)
17
severe(adjective, appearance, mean, clear, strong)
14
iron(adjective, mean, strong, hard, tough)
14
staunch(adjective, clear, strong, sound, tough)
13
solid(adjective, set, strong, hard, sound)
11
strict(adjective, strong, hard, tough, easy)
10
hidebound(adjective, firm, determined, resolute)
10
rigorous(adjective, strong, hard, tough, harsh)
10
stony(adjective, mean, hard, firm, harsh)
7
indurate(adjective, set, mean, hard, firm)
7
sturdy(adjective, set, strong, hard, sound)
6
hardened(adjective, set, hard, tough, firm)
6
single-minded(adjective, tough, firm, harsh, cruel)
6
stalwart(adjective, strong, hard, sound, tough)
5
callous(adjective, mean, hard, severe, rough)
5
dense(adjective, set, strong, hard, tough)
5
impenetrable(adjective, set, hard, tough, firm)
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APASmart Define. (2016). unyielding thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/unyielding/thesaurus/synonyms
ChicagoSmart Define. 2016. "unyielding thesaurus" https://smartdefine.org/unyielding/thesaurus/synonyms (accessed September 28, 2026).
HarvardSmart Define 2016, unyielding thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/unyielding/thesaurus/synonyms>.
MLASmart Define. "unyielding thesaurus" 10 March 2016. Web. 28 September 2026. <https://smartdefine.org/unyielding/thesaurus/synonyms>