mo·men·tous
mō-ˈmen-təs
mə-
: having great or lasting importance : consequential, significant
a momentous decision
a momentous event/occasion
The Senate begins a momentous debate on health care today …—The New York Times
Deydey usually talked about his travels, the places he'd seen and the people, the close calls and momentous encounters with animals, weather, other Anishinabeg, and best of all, ghosts.—Louise Erdrich
The late nineteenth century was strewn with inventions. Many were momentous, but few affected men and women more closely than the bicycle and its motorized offspring: motorcycle, motor-car and aeroplane.—Eugen Weber
momentously
adverb
a momentously important decision
… a … twist that is executed differently from the comic book story, but is just as dramatically and momentously presented.
—The Philippines Daily Inquirer
momentousness
noun
But other East Europeans had little time to marvel at the momentousness of the moment. Just one day after the fall of the [Berlin] Wall, Bulgaria's dour leader of 35 years, Todor Zhivkov, was ousted.
—Stephen E. Deane
mo·men·tous·ness
plural -es
: the quality or state of being momentous
impress his visitors with the momentousness … of all he had to say—H. V. Gregory
Cite this Entry
“Momentous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/momentous. Accessed 29 Oct. 2026.
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