4
inflexibility(noun, firmness, severity, harshness, strictness)
4
nicety(noun, point, care, truth, distinction)
4
ordeal(noun, trouble, blow, distress, care)
4
punctuality(noun, truth)
4
rigidness(noun, obstinacy, stubbornness)
4
severeness
4
sharpness(noun, discipline, firmness, severity, harshness)
4
toughness(noun, easy, condition, discipline, firmness)
4
validity
4
violence(noun, protest, objection, complaint)
3
acerbity(noun, discipline, firmness, severity, harshness)
3
acrimony
3
astringency
3
conscientiousness(noun, severity, harshness, strictness, exactness)
3
grievance(noun, trouble, difficulty, protest, lack)
3
meticulousness(noun, care, distinction, refinement, severity)
3
obduracy(noun, severity, harshness, strictness, obstinacy)
3
pitilessness
3
predicament(noun, difficulty, mess, situation, jam)
3
punctiliousness(noun, severity, harshness, strictness, exactness)
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APASmart Define. (2015). rigor thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/rigor/thesaurus/synonyms
ChicagoSmart Define. 2015. "rigor thesaurus" https://smartdefine.org/rigor/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, rigor thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/rigor/thesaurus/synonyms>.
MLASmart Define. "rigor thesaurus" 13 April 2015. Web. 22 September 2026. <https://smartdefine.org/rigor/thesaurus/synonyms>