momentous
adjective
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
The New York TimesDeydey 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
Louise ErdrichThe 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
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
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
Stephen E. Deane
Examples of momentous in a Sentence
My college graduation was a momentous day in my life.
a momentous occasion that will go down in the history books
Recent Examples on the Web
The New Yorker is already planning our coverage for a momentous 2026, which will include pivotal midterm elections, the start of Zohran Mamdani’s high-stakes mayoralty, and the athletic feats and political undercurrents of the Winter Olympics and the World Cup.
—David Remnick, New Yorker, 22 Dec. 2025
The European Union is on the precipice of a momentous decision on whether to use frozen Russian assets to finance more support for Ukraine, an unprecedented plan that has set up a clash between the many member states that support it and Belgium, where the lion’s share of the assets is held.
—Olesya Dmitracova, CNN Money, 17 Dec. 2025
OutKick's very own Riley Gaines was in attendance and spoke about this momentous achievement in honor of her late friend and TPUSA founder Charlie Kirk.
—Austin Perry Outkick, FOXNews.com, 12 Dec. 2025
Banks was hosting this momentous occasion in a space called ARTECHOUSE, which is one of those places where the walls are all screens, like the Sphere but nonspherical.
—Rebecca Alter, Vulture, 12 Dec. 2025
See All Example Sentences for momentous
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David Remnick, New Yorker, 22 Dec. 2025
The European Union is on the precipice of a momentous decision on whether to use frozen Russian assets to finance more support for Ukraine, an unprecedented plan that has set up a clash between the many member states that support it and Belgium, where the lion’s share of the assets is held.
—Olesya Dmitracova, CNN Money, 17 Dec. 2025
OutKick's very own Riley Gaines was in attendance and spoke about this momentous achievement in honor of her late friend and TPUSA founder Charlie Kirk.
—Austin Perry Outkick, FOXNews.com, 12 Dec. 2025
Banks was hosting this momentous occasion in a space called ARTECHOUSE, which is one of those places where the walls are all screens, like the Sphere but nonspherical.
—Rebecca Alter, Vulture, 12 Dec. 2025
See All Example Sentences for momentous
Cite this Entry
“Momentous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/momentous. Accessed 31 Dec. 2025.
Copy CitationKids Definition
momentous
adjective
mo·men·tous
mō-ˈment-əs
: very important
a momentous decision
momentously
adverb
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