mil·​len·​ni·​um | \ mə-ˈle-nē-əm How to pronounce millennium (audio) \
plural millennia\ mə-​ˈle-​nē-​ə How to pronounce millennia (audio) \ or millenniums

Definition of millennium

1a : the thousand years mentioned in Revelation (see revelation sense 3) 20 during which holiness is to prevail and Christ is to reign on earth
b : a period of great happiness or human perfection
2a : a period of 1000 years especially : one reckoned from the beginning of the Christian era at the start of the third millennium
b : a 1000th anniversary or its celebration In 2015 the city of Leipzig, Germany, celebrated its millennium.

Keep scrolling for more

Did You Know?

Since in Latin mille means "thousand", a millennium lasts 1,000 years. Thus, we're living today at the beginning of the third millennium since the birth of Christ. But some religious sects, relying on a prophecy in the biblical Book of Revelation, speak of a coming millennium when Jesus will return to reign on earth for 1,000 years, evil will be banished, and all will live in peace and happiness. Members of these sects who keep themselves in a constant state of preparedness are called millenarians or millennialists.

Examples of millennium in a Sentence

The book describes the changes that have occurred in the landscape over many millennia. The year 2000 was celebrated as the beginning of the third millennium.
Recent Examples on the Web At the start of the First World War, government consumption in Britain jumped from 8% of GDP in 1913 to nearly 40% in 1917, according to analysis of the Bank of England’s millennium data set. Sree Ramaswamy, Fortune, "What history can teach us about the economic impact of the coronavirus pandemic," 1 June 2020 Inside, there was a figurine of the goddess, sitting on a donkey and carrying her jar of cooling liquid—the way she has been depicted for a millennium. Siddhartha Mukherjee, The New Yorker, "How Does the Coronavirus Behave Inside a Patient?," 26 Mar. 2020 In 2013, with a few words in Latin, Pope Benedict XVI did what no pope had done in more than half a millennium: announced his resignation., "This day in history," 11 Feb. 2020 Half a millennium on, the behavior of viruses like smallpox or 2019-nCoV hasn’t changed, but the behavior of their human hosts and victims has. Time, "The Coronavirus Outbreak Should Bring Out the Best in Humanity," 8 Feb. 2020 Somehow, nearly a millennium later, Hamoutal has been remembered and honored. Sam Sacks, WSJ, "Fiction: David, Bathsheba and Sir Thomas Wyatt," 31 Jan. 2020 The oldest known bowstrings outside of Ötzi’s come from Egyptian graves dated to between 2200 and 1900 B.C., making the Iceman’s bowstring, dated to between 3300 and 3100 B.C, the oldest by a millennium. Theresa Machemer, Smithsonian Magazine, "What We Can Learn From Ötzi the Iceman’s Hunting Pack," 3 Jan. 2020 Make a Pilgrimage People have been walking the Camino de Santiago in Spain for over a millennium. Megan Michelson, Outside Online, "7 Adventures to Start the New Decade with a Bang," 17 Dec. 2019 The research suggests an alarming pace of change for the Earth's second-largest body of ice, which could theoretically drive over 20 feet of sea-level rise over a millennium. Chris Mooney, Anchorage Daily News, "Greenland’s rapidly increasing ice losses are now in line with highest sea-level scenario, scientists say," 10 Dec. 2019

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

See More

First Known Use of millennium

circa 1638, in the meaning defined at sense 1a

History and Etymology for millennium

New Latin, from Latin mille thousand + New Latin -ennium (as in biennium)

Keep scrolling for more

Learn More about millennium

Time Traveler for millennium

Time Traveler

The first known use of millennium was circa 1638

See more words from the same year

Statistics for millennium

Last Updated

23 Jun 2020

Cite this Entry

“Millennium.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2020.

Keep scrolling for more

More Definitions for millennium


How to pronounce millennium (audio)

English Language Learners Definition of millennium

: a period of 1,000 years
: a period of a thousand years counted from the beginning of the Christian era


mil·​len·​ni·​um | \ mə-ˈle-nē-əm How to pronounce millennium (audio) \
plural millennia\ -​nē-​ə \ or millenniums

Kids Definition of millennium

1 : a period of 1000 years
2 : a 1000th anniversary or its celebration

Other Words from millennium

millennial \ -​nē-​əl \ adjective

Keep scrolling for more

Comments on millennium

What made you want to look up millennium? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

Original Meanings Quiz

  • rembrandt painting a young scholar and his tutor
  • Which of the following is the earliest known sense of the word awe?
Spell It

Can you spell these 10 commonly misspelled words?

Bee Cubed

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!