[ mɪ'lɛnɪəm ]
■ noun ( plural millennia -nɪə or ~s )
1》 a period of a thousand years, especially when calculated from the traditional date of the birth of Christ.
↘( the ~ ) Christian Theology the prophesied thousand-year reign of Christ at the end of the age (Rev. 20:1–5).
↘a utopian period.
2》 an anniversary of a thousand years.
3》 ( the ~ ) the point at which one period of a thousand years ends and another begins.
Derivatives
millennial adjective
Origin
C17: mod. L., from L. mille 'thousand', on the pattern of biennium .
Usage
The correct spelling is ~ , with two n s. The spelling with one n is a common error, formed by analogy with other similar words correctly spelled with only one n , such as millenarian .