87 entries under rigid topic. ×

2
steadfast(adjective, hard, resolute, inflexible)
2
unadaptable(adjective, hard, resolute, inflexible)
1
by the book(expression, adjective, idiom, strong, hard)
1
dead set(expression, adjective, tough, severe, firm)
1
disciplinary(adjective, strong, hard, tough, severe)
1
dyed-in-the-wool(adjective, set, strong, hard, tough)
1
forbidding(adjective, strong, hard, tough, severe)
1
grievous(adjective, hard, tough, severe, harsh)
1
hard-boiled(adjective, strong, hard, tough, severe)
1
iron-fisted(adjective, tough, severe, firm, harsh)
1
powerful(adjective, severe, harsh, tight)
1
resolved
1
set(adjective, hard, tough, severe, firm)
1
steady
1
stickling(adjective, tough, severe, firm, harsh)
1
straight(adjective, tough, correct, severe, firm)
1
stuffy(adjective, tough, severe, firm, harsh)
1
tense
1
uncompliant(adjective, hard, resolute, inflexible)
1
unpermissive(adjective, hard, tough, severe, rough)
10 years ago|17k views|share |citing 
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>