6
respectable(adjective, substantial, large, admired, respected)
6
salient(adjective, extraordinary, unusual, important, substantial)
6
solemn(adjective, importance, valuable, main, notable)
6
sound(adjective, large, forceful, accepted, established)
6
tidy(adjective, substantial, large, considerable)
6
urgent(adjective, clear, tough, severe, big)
6
valid(adjective, good, clear, sensible, fair)
5
bigwig(adjective, importance, valuable, main, notable)
5
ample(adjective, substantial, large, considerable)
5
augural(characteristic, prediction, telling, ominous, revealing)
5
authoritative
5
big time(adjective, importance, main, extremely significant)
5
celebrated(adjective, outstanding, prominent, notable, distinguished)
5
constitutive(adjective, importance, valuable, main, notable)
5
denotative(adjective, characteristic, representative, telling, ominous)
5
earnest(adjective, importance, valuable, main, notable)
5
effective(adjective, strong, sharp, important, powerful)
5
effectual(adjective, sharp, useful, beneficial, advantageous)
5
eminent(adjective, good, extraordinary, important, strange)
5
evidence(noun, feature, characteristic, mark, sign)
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APASmart Define. (2016). significant thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/significant/thesaurus/synonyms
ChicagoSmart Define. 2016. "significant thesaurus" https://smartdefine.org/significant/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, significant thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/significant/thesaurus/synonyms>.
MLASmart Define. "significant thesaurus" 4 March 2016. Web. 21 September 2026. <https://smartdefine.org/significant/thesaurus/synonyms>