millennium

noun

mil·​len·​ni·​um mə-ˈle-nē-əm 

plural millennia mə-ˈle-nē-ə  or millenniums

1

a

: 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

2

a

: 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.

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

The divide has drawn comparisons to the Great Schism, which a millennium ago separated the Orthodox East and the Catholic West. —Robert F. Worth, The Atlantic, 10 Apr. 2024

Given that the chapel has stood for half a millennium — the product of a 70-year construction project under four kings: Henry VI, VII and VIII, plus Richard III — the furor over the solar panels will end up being at most a transitory distraction. —Mark Landler, New York Times, 30 Mar. 2024

Malta has temples that date back a half millennium older than Stonehenge. —Joshua Rapp Learn, Discover Magazine, 27 Mar. 2024

Half a millennium ago, in what is now Peru, the indigenous Uros people used thatches of reeds to build floating islets in Lake Titicaca, likely as a safe haven from Incan encroachment. —Kyle Chayka, The New Yorker, 25 Mar. 2024

Even before dinosaurs, jellyfish were on Earth – and in its seas and oceans – for millennia, according to National Geographic. —Olivia Munson, USA TODAY, 30 Mar. 2024

Into the earth the shovels go, and out spring various Etruscan artifacts, mostly pottery, that were entombed, roughly two millennia ago, alongside their deceased owners. —Justin Chang, The New Yorker, 28 Mar. 2024

Humans have observed and tracked solar eclipses for millennia. —Elizabeth Gamillo, Discover Magazine, 28 Mar. 2024

The next time this calendar event happens will be on April 20, 3024, another millennium from now. —The Arizona Republic, 28 Mar. 2024

Word History

Etymology

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

First Known Use

circa 1638, in the meaning defined at sense 1a

Phrases Containing millennium

• the millennium

Kids Definition

millennium

noun

mil·​len·​ni·​um mə-ˈlen-ē-əm 

plural millennia

-ē-ə

or millenniums

1

a

: a period of 1000 years

b

: a 1000th anniversary or its celebration

2

: a period of great happiness

millennial

-ē-əl

adjective