2
fatal(adjective, decide)
2
full of incident(expression, idiom, eventuality)
2
fundamental(adjective, important, significant, substantial, serious)
2
illustrious(adjective, outstanding, prominent, notable, distinguished)
2
liberal
2
life changing
2
major-league(strong, important, powerful, significant, large)
2
marked(adjective, great, solid, extraordinary, superior)
2
meaning
2
meritorious(adjective, bad, great, excellent, superior)
2
much(significant, substantial, large)
2
of concern
2
of moment(expression, adjective, big, important, substantial)
2
ominous(adjective, heavy, significant, acute, dangerous)
2
paramount(adjective, good, big, important, significant)
2
phenomenal(adjective, bad, great, excellent, solid)
2
preeminent(adjective, bad, great, excellent, solid)
2
red-letter(adjective, great, extraordinary, superior, unusual)
2
sedate(big, heavy, substantial)
2
sober(adjective, energetic, big, heavy, substantial)
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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>