Dictionary.com
definitions
  • synonyms

momentous

[moh-men-tuh s]
See more synonyms on Thesaurus.com
adjective
  1. of great or far-reaching importance or consequence: a momentous day.

Origin of momentous

First recorded in 1645–55; moment + -ous
Related formsmo·men·tous·ly, adverbmo·men·tous·ness, nounun·mo·men·tous, adjectiveun·mo·men·tous·ly, adverbun·mo·men·tous·ness, noun

Synonyms

See more synonyms on Thesaurus.com
vital, critical, crucial, serious. See heavy.

Antonyms

trivial, trifling.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for momentous

Contemporary Examples

Historical Examples


British Dictionary definitions for momentous

momentous

adjective
  1. of great significance
Derived Formsmomentously, adverbmomentousness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for momentous

adj.

1650s, from moment + -ous to carry the sense of "important" while momentary kept the meaning "of an instant of time." Related: Momentously; momentousness.

Online Etymology Dictionary, © 2010 Douglas Harper