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

They grow about a centimeter or two a year and by sampling cores at the millimeter scale, the team was able to develop windows of monthly temperature records scattered across the past millennium.

From Barron's ● Aug. 27, 2026

A trio of beloved bluegrass albums, “The Grass Is Blue,” “Little Sparrow” and “Halos & Horns,” around the turn of the millennium reestablished her as a performer with extensive roots in rural America.

From Los Angeles Times ● Aug. 25, 2026

Gregory thinks of how Iceland's first settlers must have felt witnessing such a phenomena more than a millennium ago, a time of mythological rather than scientific explanation.

From BBC ● Aug. 9, 2026

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

From Salon ● Jul. 12, 2026

It is also not restricted to our time: Sumerian cylinder seals from the third millennium b.c. and Taoist flags in prerevolutionary China displayed constellations.

From "Cosmos" by Carl Sagan

"We see continuity here," explains Frank Maixner, director of the Institute for Mummy Studies at Eurac Research: "These yeasts have accompanied Ötzi on his long journey through the millennia."

From Science Daily ● Aug. 7, 2026

This fog-shrouded patch of coastal forest in the heart of Yurok Country was tended by the tribe for millennia.

From Los Angeles Times ● Jul. 28, 2026

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

From Barron's ● Jul. 14, 2026

Its champions, though, have been around for millennia.

From The Wall Street Journal ● Jul. 6, 2026

The Americas were filled with an enthusiastically diverse assortment of peoples who had knocked about the continents for millennia.

From "1491" by Charles C. Mann

Many of these seemingly otherworldly volcanic fields are adorned with archaeological remains — from small dwellings to colossal animal-corralling structures called kites — that date back millenniums.

From New York Times ● Apr. 17, 2024

Three millenniums ago, a small, prosperous farming community briefly flourished in the freshwater marshes of eastern England.

From New York Times ● Mar. 19, 2024

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

In the cold dark of a November night, beneath the jagged cliffs of Zion National Park, Dani Hsia posed a question that mystics and religious thinkers have pondered for millenniums.

From Los Angeles Times ● Nov. 30, 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