Definitions

momentous

[moh-men-tuhs] / moʊˈmɛn təs /

ADJECTIVE

important; serious

Synonyms

STRONGEST

consequential crucial decisive eventful far-reaching fateful historic meaningful memorable notable pivotal significant weighty

WEAK

big chips are down considerable critical earth-shaking earth-shattering epochal grave heavy heavy number material of moment outstanding substantial vital

Antonyms

STRONGEST

inconsequential insignificant meaningless ordinary trivial uneventful unimportant unnoteworthy unremarkable unsubstantial

WEAK

immaterial trifling

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

And it didn’t take earnings or fresh guidance or even a momentous announcement to make that happen.

From Barron's • May 29, 2026

She made similarly momentous visits to Los Angeles and Inyo counties.

From Los Angeles Times • May 18, 2026

During a momentous power struggle in 2017, Sutskever and Brockman proposed giving Musk more than half of OpenAI’s equity.

From The Wall Street Journal • May 18, 2026

Hastings, and others involved in that momentous afternoon, have recalled what he was like and the picture was, at times, hilarious.

From BBC • May 17, 2026

And it was during one of those flights that our friends made a truly momentous discovery.

From "The Wild Robot Protects" by Peter Brown

Vocabulary lists containing momentous

The SAT: Words to Capture Tone, List 3

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The New SAT: Words to Capture Tone

Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!

100 SAT Words Beginning with "M"

Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!