6
capital(adjective, bad, great, excellent, important)
6
earthshaking(adjective, important)
6
iconic(adjective, feature, state, characteristic, most important)
6
integral(adjective, importance, main, extremely significant)
6
main(adjective, good, bad, great, excellent)
5
cogent(adjective, energetic, significant, effective, forceful)
5
distinguished(adjective, bad, great, excellent, extraordinary)
5
eminent(adjective, good, bad, great, excellent)
5
groundbreaking(adjective, radical, innovative, milestone, landmark)
5
heavy(adjective, great, tough, severe, big)
5
inescapable(adjective, feature, state, characteristic, most important)
5
necessary(adjective, important, substantial, valuable, essential)
5
overriding(adjective, feature, state, characteristic, most important)
5
pressing(adjective, tough, severe, big, heavy)
5
primary(adjective, superior, big, unusual, important)
4
epochal(adjective, important, significant, historic)
4
flagship(adjective, feature, state, characteristic, most important)
4
heavyweight(adjective, big, heavy, important, outstanding)
4
life-changing
4
pregnant(adjective, significant, expressive, meaningful, weighty)
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APASmart Define. (2016). momentous thesaurus. Retrieved September 30, 2026, from https://smartdefine.org/momentous/thesaurus/synonyms
ChicagoSmart Define. 2016. "momentous thesaurus" https://smartdefine.org/momentous/thesaurus/synonyms (accessed September 30, 2026).
HarvardSmart Define 2016, momentous thesaurus, Smart Define, viewed 30 September, 2026, <https://smartdefine.org/momentous/thesaurus/synonyms>.
MLASmart Define. "momentous thesaurus" 1 April 2016. Web. 30 September 2026. <https://smartdefine.org/momentous/thesaurus/synonyms>