127 entries under tough topic. ×

1
effortful(adjective, hard, severe, rough)
1
emotionless(adjective, rational, straightforward, sober)
1
exacting(adjective, hard, severe, rough)
1
exhausting(adjective, hard, severe, rough)
1
exigent(adjective, hard, difficult, big)
1
factual(adjective, rational, straightforward, sober)
1
fatiguing(adjective, severe, rough, difficult)
1
feasible(adjective, rational, straightforward, sober)
1
flat(adjective, rational, straightforward, sober)
1
flinty(adjective, close, strong, hard)
1
hang-tough(adjective, strong, hard, severe)
1
hard-boiled(adjective, calm, strong, hard)
1
hard-core(adjective, strong, hard, severe)
1
hard-line(adjective, strong, hard, severe)
1
hard-shell(adjective, strong, hard, severe)
1
hardheaded(adjective, strong, hard, severe)
1
impersonal(adjective, rational, straightforward, sober)
1
importunate(hard, big, important, substantial)
1
inflexible(adjective, strong, hard, severe)
1
irksome(adjective, severe, rough, difficult)
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APASmart Define. (2016). serious thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/serious/thesaurus/synonyms
ChicagoSmart Define. 2016. "serious thesaurus" https://smartdefine.org/serious/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2016, serious thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/serious/thesaurus/synonyms>.
MLASmart Define. "serious thesaurus" 24 February 2016. Web. 29 September 2026. <https://smartdefine.org/serious/thesaurus/synonyms>