119 entries under severe topic. ×

93
grave(adjective, calm, dull, quiet, help)
43
weighty(adjective, good, dull, hard, great)
39
solemn(adjective, calm, dull, quiet, cool)
37
important(adjective, good, great, extraordinary)
37
earnest(noun, adjective, calm, dull, work)
32
critical(adjective, hard, great, tough)
31
sad(adjective, hard, difficult, complex, importance)
30
sober(adjective, calm, dull, quiet, cool)
28
momentous(adjective, good, great, extraordinary)
26
hard(adjective, strong, tough, easy)
23
sedate(adjective, calm, dull, cool)
22
staid(adjective, calm, dull, set, cool)
20
grim(adjective, dull, strong, hard, tough)
19
cruel(adjective, strong, hard, tough)
19
hard-nosed(adjective, strong, hard, tough)
19
heavy(adjective, strong, hard, great, tough)
19
vital(adjective, great, importance, big)
15
dangerous(adjective, help, bad, great)
15
crucial(adjective, great, extraordinary, big)
15
meaningful(adjective, good, great, extraordinary)
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APASmart Define. (2016). serious thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/serious/thesaurus/synonyms
ChicagoSmart Define. 2016. "serious thesaurus" https://smartdefine.org/serious/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, serious thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/serious/thesaurus/synonyms>.
MLASmart Define. "serious thesaurus" 24 February 2016. Web. 23 September 2026. <https://smartdefine.org/serious/thesaurus/synonyms>