15
important(adjective, substantial, serious, valuable)
13
royal
10
significant(adjective, important, substantial, unimportant, serious)
10
major(adjective, dull, big, substantial, serious)
10
substantial(adjective, serious)
9
consequential(adjective, small, substantial, serious)
9
essential(adjective, substantial, serious)
8
weighty(adjective, light, important, substantial, serious)
8
momentous(adjective, important, ordinary, insignificant)
7
serious(adjective, substantial, weighty, crucial)
6
key(insignificant, unimportant)
6
material
6
titanic
6
appreciable
6
crucial(adjective, important, critical)
6
eventful(adjective, significant, busy)
6
fundamental(adjective, important, basic)
6
gargantuan
6
great
6
smart
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APASmart Define. (2015). trivial thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/trivial/thesaurus/antonyms
ChicagoSmart Define. 2015. "trivial thesaurus" https://smartdefine.org/trivial/thesaurus/antonyms (accessed September 26, 2026).
HarvardSmart Define 2015, trivial thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/trivial/thesaurus/antonyms>.
MLASmart Define. "trivial thesaurus" 10 April 2015. Web. 26 September 2026. <https://smartdefine.org/trivial/thesaurus/antonyms>