millennium

American  

[mi-len-ee-uhm] / mɪˈlɛn i əm /

noun

millenniums, plural millennia plural

1. a period of 1,000 years.

   This great stone monument has seen it all—hardship, plenty, and everything in between—over a millennium and a half.

2. the year 2000, or the turn of the 21st century.

   In 1995, approaching the millennium, the city covered nearly 67,000 acres and had a population of over 1 million.

3. Christianity. the millennium, the period of 1,000 years during which Christ will reign on earth, as an interpretation of a vision set forth by the apostle John in the book of Revelation. Also the Millennium

4. a period of general righteousness and happiness, especially in the indefinite future.

5. a thousandth anniversary.

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millennium British  

/ mɪˈlɛnɪəm /

noun

1. Christianity the period of a thousand years of Christ's awaited reign upon earth

2. a period or cycle of one thousand years

3. a time of peace and happiness, esp in the distant future

4. a thousandth anniversary

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millennium Cultural  

1. A period of a thousand years foretold in the Book of Revelation. During the millennium, those who have been faithful to Jesus and who have not worshiped the Antichrist will reign with Jesus over the Earth. According to the Book of Revelation, the millennium will precede the final battle for control of the universe; Judgment Day will come afterward.

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Discover More

Figuratively, a “millennium” is a period of great justice and happiness on Earth.

The meaning of the Bible's (see also Bible) words about the millennium has been much debated by Christians (see also Christian). Prophecies about the millennium are part of the basic doctrine of several denominations, including Jehovah's Witnesses.

Other Word Forms

Derived Forms

• millennialist
  noun
• millennial
  adjective
• millennially
  adverb

Inflected Forms

Nouns

• millennia
  plural
• millenniums
  plural

Etymology

Origin of millennium

First recorded in 1630–40; from New Latin, equivalent to Latin mill(e) “a thousand” + -ennium, extracted from biennium, triennium, etc.

Explanation

A decade means ten years, a century means a hundred, and millennium means a thousand. Think: a decade of marriage, the new millennium. In Latin, in the Romance languages, and in the metric system, mille refers to a thousand. A millimeter is a thousandth of a meter, a milliliter a thousandth of a liter, a millennium is a thousand years. Think of the number "one million" as a thousand thousands, and you'll get the idea.

Example Sentences

See Examples For:

millennium millennia millenniums

At 2.6 points, his 2018 reelection margin marked Texas’ closest statewide race this millennium.

From Salon ● Jul. 12, 2026

With the U.S. celebrating a quarter of a millennium as an independent republic, Bank of America has looked at its record of economic growth and its returns for investors.

From MarketWatch ● Jul. 3, 2026

The mere millionaires saw their wealth grow at an annual rate of 4% adjusted for inflation since the start of the millennium, UBS said.

From Barron's ● Jun. 30, 2026

How did the plague stick around for nearly half a millennium after the initial wave, causing repeated outbreaks?

From The Wall Street Journal ● Jun. 12, 2026

When Boobie Miles returned to the football field, no one called out his name with those bellowing chants that had rocked the Watermelon Feed in a moment that seemed like a millennium before.

From "Friday Night Lights: A Town, A Team, And A Dream" by H.G. Bissinger

Cultivated for millennia, Armenia's famed apricots were known to ancient Romans as the "Armenian apple."

From Barron's ● Jul. 14, 2026

But religious traditions have spent millennia on exactly those concerns.

From The Wall Street Journal ● Jul. 9, 2026

Although Cave 338 was not used as a permanent settlement, the repeated returns over millennia suggest that the location held significant value for prehistoric groups.

From Science Daily ● Jun. 3, 2026

Reid said if several centimetres are lost to fire, then "you're losing decades, centuries, potentially millennia of peatland".

From BBC ● May 2, 2026

For millennia, he thought, they had existed almost without change in a landscape unmarked by their presence.

From "1491" by Charles C. Mann

The off-white form of the rustic terracotta jar, shattered over millenniums and fastidiously reassembled, is elegantly decorated in rich brown and black designs, including bursts of rosettes and abstract squiggles.

From Los Angeles Times ● Sep. 10, 2025

It would guide scientists in their understanding of our still-unfolding present for generations, perhaps even millenniums, to come.

From Seattle Times ● Mar. 9, 2024

After a religious revolt against robots millenniums before the start of the series, the use of intelligent machines was banned.

From New York Times ● Feb. 29, 2024

Or are you purchasing an item, wrapping, bag or bow that will be used once, then sent off to a landfill where it will sit, undisturbed, for the next several millenniums?

From Los Angeles Times ● Dec. 31, 2023

Collectively, memorable events have caused the ever-quickening pace of change during the past five millenniums, which begin with what we call the ancient world.

From "History of Art, Volume 1" by H.W. Janson