87 entries under rigid topic. ×

5
unsparing(adjective, strong, hard, tough, severe)
4
acrimonious(adjective, tough, severe, harsh, grim)
4
determined(adjective, severe, harsh, solid, intense)
4
immutable(adjective, hard, resolute, inflexible)
4
prudish(adjective, tough, severe, firm, harsh)
4
resolute(adjective, hard, intense, inflexible)
4
strait-laced(adjective, tough, severe, firm, harsh)
4
strong(adjective, hard, tough, severe, sturdy)
4
stubborn(adjective, strong, hard, tough, severe)
3
authoritarian(adjective, strong, hard, tough, severe)
3
fixed(adjective, hard, severe, stiff)
3
taut
2
concrete(adjective, correct, solid, exact, proper)
2
hard-nosed(adjective, strong, hard, tough, severe)
2
intractable(adjective, hard, resolute, inflexible)
2
iron(hard, resolute, inflexible, strict)
2
picky(adjective, tough, severe, fine, firm)
2
poignant(adjective, severe, harsh, unpleasant, vicious)
2
solid(adjective, complete, correct, severe, harsh)
2
square(adjective, tough, severe, firm, harsh)
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APASmart Define. (2016). rigorous thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/rigorous/thesaurus/synonyms
ChicagoSmart Define. 2016. "rigorous thesaurus" https://smartdefine.org/rigorous/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, rigorous thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/rigorous/thesaurus/synonyms>.
MLASmart Define. "rigorous thesaurus" 26 February 2016. Web. 24 September 2026. <https://smartdefine.org/rigorous/thesaurus/synonyms>