26
unimportant(adjective, dull, weak, value, substantial)
15
insignificant(adjective, important, significant, substantial)
13
lightweight(adjective, characteristic, weakness, inconsequential, insignificance)
10
unknown(adjective, dull, weak, little)
9
trivial(adjective, important, substantial, serious)
7
inappreciable(adjective, dull, weak, little)
7
sub-par(adjective, characteristic, weakness, insignificance)
6
inconsequential(adjective, characteristic, weakness, insignificant, insignificance)
6
slight(adjective, small, insignificant, large)
6
subpar(adjective, characteristic, weakness, insignificance)
5
powerless(adjective, dull, weak, little)
5
niggling(adjective, characteristic, weakness, insignificance)
4
small(adjective, dull, weak, unimportant, little)
4
footling(adjective, characteristic, weakness, insignificance)
4
negligible(adjective, characteristic, weakness, insignificant, insignificance)
4
flimsy(adjective, characteristic, weakness, insignificance)
4
helpless(adjective, characteristic, weakness, insignificance)
4
ineffective(adjective, characteristic, weakness, common, insignificance)
4
marginalized(adjective, characteristic, weakness, insignificance)
4
mini(adjective, characteristic, weakness, insignificance)
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APASmart Define. (2016). important thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/important/thesaurus/antonyms
ChicagoSmart Define. 2016. "important thesaurus" https://smartdefine.org/important/thesaurus/antonyms (accessed September 22, 2026).
HarvardSmart Define 2016, important thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/important/thesaurus/antonyms>.
MLASmart Define. "important thesaurus" 29 March 2016. Web. 22 September 2026. <https://smartdefine.org/important/thesaurus/antonyms>