The DICT Development Group

  Millennium \Mil*len"ni*um\ (m[i^]l*l[e^]n"n[i^]*[u^]m), n. [LL.,
     fr. L. mille a thousand + annus a year. See Mile, and
     Annual.]
     1. A period of one thousand years.
        [1913 Webster]
  
     2. Specifically: The period of a thousand years mentioned in
        the twentieth chapter of Revelation, during which holiness
        is to be triumphant throughout the world. Some believe
        that, during this period, Christ will reign on earth in
        person with his saints.
        [1913 Webster]
  
     3. Hence: A long period of happiness, righteousness, and
        prosperity, usually considered as being in the indefinite
        future.
        [PJC]
  
     4. A thousandth anniversary; especially, Each first day of
        January falling in a year which is a multiple of one
        thousand, such as in 1000 a. d. or 2000 a. d.; as, the
        second millenium will be celebrated on January 1, 2000;
        also used attributively, as a millenium celebration.
  
     Note: Technically, if the calendar of the Common Era (Anno
           Domini) is considered as beginning on January 1, 1 a.
           d., then the millenium will fall in each year ending in
           001, as in 1001 a. d. or January 1, 2001 a. d.. However
           in the common culture, the change of the first digit of
           the year from 1 to 2, as from 1999 to 2000 is
           considered as the more symbolic event, especially since
           the dating of the beginning of the Christian era is
           somewhat arbitrary, having been an attempt to fix the
           date of the birth of Christ, and being considered by
           scholars as being in error by as much as five years.
           [PJC]

  millennium
       n 1: a span of 1000 years
       2: (New Testament) in Revelations it is foretold that those
          faithful to Jesus will reign with Jesus over the earth for
          a thousand years; the meaning of these words have been
          much debated; some denominations (e.g. Jehovah's
          Witnesses) expect it to be a thousand years of justice and
          peace and happiness
       3: the 1000th anniversary (or the celebration of it)
       [also: millennia (pl)]

  124 Moby Thesaurus words for "millennium":
     Agapemone, Arcadia, Big Rock-Candy Mountain, Canaan,
     Cloudcuckooland, Cockaigne, Eden, Eldorado, Erewhon, G,
     Garden of Eden, Goshen, Happy Valley, Land of Youth, Laputa, M,
     Never-Never-land, Neverland, New Atlantis, Pandemonium, Quivira,
     Saturnia regna, Saturnian age, Shangri-la, Utopia, abundant year,
     academic year, age of Aquarius, annum, bissextile year,
     calendar month, calendar year, century, chiliad, chiliagon,
     chiliahedron, chiliarch, chiliarchia, cloudland, common year, day,
     decade, decennary, decennium, defective year, dreamland, dystopia,
     era of prosperity, faerie, fair weather, fairyland, fiscal year,
     fortnight, golden age, golden era, golden time, good times, grand,
     halcyon days, heaven, heyday, hour, kakotopia, kilo, kilocycle,
     kilogram, kilohertz, kiloliter, kilometer, kingdom come, lakh,
     land of dreams, land of enchantment, land of faerie,
     land of plenty, land of promise, leap year, lotus land,
     lunar month, lunar year, lunation, luster, lustrum, man-hour,
     microsecond, millepede, milligram, milliliter, millisecond, minute,
     moment, month, moon, myriad, one hundred thousand, palmy days,
     paradise, piping times, promised land, prosperity, quarter,
     quinquennium, regular year, reign of Saturn, rosy era, second,
     semester, session, sidereal year, solar year, sun, sunshine,
     ten thousand, term, thou, thousand, trimester, twelvemonth, utopia,
     week, weekday, wonderland, yard, year
  
  

  Millennium
     a thousand years; the name given to the era mentioned in Rev.
     20:1-7. Some maintain that Christ will personally appear on
     earth for the purpose of establishing his kingdom at the
     beginning of this millennium. Those holding this view are
     usually called "millenarians." On the other hand, it is
     maintained, more in accordance with the teaching of Scripture,
     we think, that Christ's second advent will not be premillennial,
     and that the right conception of the prospects and destiny of
     his kingdom is that which is taught, e.g., in the parables of
     the leaven and the mustard-seed. The triumph of the gospel, it
     is held, must be looked for by the wider and more efficient
     operation of the very forces that are now at work in extending
     the gospel; and that Christ will only come again at the close of
     this dispensation to judge the world at the "last day." The
     millennium will thus precede his coming.
     

  MILLENNIUM, n.  The period of a thousand years when the lid is to be
  screwed down, with all reformers on the under side.