121 entries under rigid topic. ×

13
determined(adjective, clear, strong, hard, severe)
12
heavy(noun, adjective, good, person, dull)
12
rocky(adjective, firm, stiff, troubled)
12
steadfast(adjective, calm, clear, strong, severe)
11
fixed(adjective, mean, strong, hard, sound)
11
relentless(adjective, mean, strong, hard, severe)
11
rigorous(adjective, strong, hard, severe, rough)
10
unrelenting(adjective, mean, strong, hard, severe)
9
steady(adjective, calm, strong, sound, heavy)
9
stringent(adjective, hard, severe, firm, difficult)
8
austere(adjective, strong, hard, severe, sharp)
8
hard-line(adjective, characteristic, strong, hard, rough)
8
unsparing(adjective, strong, hard, severe, rough)
7
dense(adjective, person, set, body, strong)
7
inexorable(adjective, mean, strong, hard, firm)
7
set(verb, adjective, calm, strong, hard)
7
unwavering(adjective, calm, strong, secure, firm)
6
authoritarian(noun, adjective, strong, hard, severe)
6
critical(adjective, hard, difficult, harsh, important)
5
rocklike(adjective, firm, difficult, stiff)
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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>