mo·​men·​tous | \ mō-ˈmen-təs, mə-\

Definition of momentous 

: important, consequential a momentous decision a momentous event

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Other Words from momentous

momentously adverb
momentousness noun

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

If India can maintain its pace, the impact on global well-being will be just as momentous, given that India’s population should soon pass China’s. Greg Ip, WSJ, "The World Is Getting Quietly, Relentlessly Better," 2 Jan. 2019 The ruling against segregation was momentous, a win for the lives of 5,000 children and their parents, and for the Mexican-American community. Mariana Viera, Teen Vogue, "How Méndez vs. Westminster Helped End Segregated Schools for Latinx Children in 1940s California," 12 Oct. 2018 Today is a momentous day for American Horror Story fans. Emma Dibdin, Harper's BAZAAR, "Jessica Lange Is Returning To American Horror Story in Season 8," 3 Aug. 2018 Photo: Sonos Today is a momentous day for US smart speaker company Sonos, which is marking is sixteenth year of existence with an IPO set to value it at around $1.5 billion. Vlad Savov, The Verge, "Sonos redesigned the Nasdaq opening bell to mark IPO," 2 Aug. 2018 To declare that the experience was riveting, momentous, and utterly unique would be a triumph of understatement, but the sentiment would be echoed by anyone who ever worked for and with the man. Town & Country, ""Got the Snaps?"," 13 June 2015 The new movie also hints that the five-part series will take us into WWII, so J.K. Rowling seems to be working in momentous historical eventss from each time period. Kelsey Stiegman, Seventeen, "There’s a Hidden Titanic Reference in Fantastic Beasts: the Crimes of Grindelwald and You Totally Missed It," 16 Nov. 2018 The sites offer a glimpse of the everyday life of people living at this time of momentous transition. Mark Barna, Discover Magazine, "When Farmers and Foragers First Met," 24 Oct. 2018 Last October, Swiss archaeologists were presented with a momentous and possibly history-making discovery: a bronze hand with a gold cuff glued to its wrist, alongside what appeared to be a withered dagger and a human rib. Sam Blum, Popular Mechanics, "3,500-Year-Old Swiss Relic Might Be Europe's Oldest Bronze Sculpture," 26 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'momentous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of momentous

1656, in the meaning defined above

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Statistics for momentous

Last Updated

10 Jan 2019

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Time Traveler for momentous

The first known use of momentous was in 1656

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More Definitions for momentous



English Language Learners Definition of momentous

: very important : having great or lasting importance


mo·​men·​tous | \ mō-ˈmen-təs \

Kids Definition of momentous

: very important a momentous decision

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