918 entries under adjective topic. ×

7
decisive(great, severe, firm, extraordinary)
7
dedicated(complete, warm, total, passionate)
7
detrimental(importance, main, dangerous, extremely significant)
7
devoted(complete, warm, total, passionate)
7
donnish(importance, valuable, main, notable)
7
exciting(importance, valuable, main, notable)
7
far reaching(importance, valuable, main, notable)
7
genuine(set, open, honest, total)
7
haughty(importance, valuable, main, notable)
7
high(important, prominent, exalted)
7
high-up(importance, valuable, main, notable)
7
key-note(importance, valuable, main, notable)
7
perilous(bad, heavy, uncertain, significant)
7
precious(importance, main, greatness, extremely significant)
7
red hot(importance, main, extremely significant)
7
relevant(importance, big, significant, substantial)
7
significative(importance, valuable, main, notable)
6
ardent(complete, keen, warm, total)
6
big league(importance, important, main, extremely significant)
6
businesslike(work, heavy, somber, efficient)
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APASmart Define. (2016). serious thesaurus. Retrieved September 27, 2026, from https://smartdefine.org/serious/thesaurus/synonyms
ChicagoSmart Define. 2016. "serious thesaurus" https://smartdefine.org/serious/thesaurus/synonyms (accessed September 27, 2026).
HarvardSmart Define 2016, serious thesaurus, Smart Define, viewed 27 September, 2026, <https://smartdefine.org/serious/thesaurus/synonyms>.
MLASmart Define. "serious thesaurus" 24 February 2016. Web. 27 September 2026. <https://smartdefine.org/serious/thesaurus/synonyms>