Definition of millennium noun from the Oxford Advanced Learner's Dictionary



    BrE BrE//mɪˈleniəm//
    ; NAmE NAmE//mɪˈleniəm//
    (pl. millennia
    BrE BrE//mɪˈleniə//
    ; NAmE NAmE//mɪˈleniə//
    , millenniums)
    jump to other results
  1. 1a period of 1 000 years, especially as calculated before or after the birth of Christ the second millennium AD For millennia, it was accepted that the earth was at the centre of the universe.
  2. 2the millennium the time when one period of 1 000 years ends and another begins How did you celebrate the millennium?
  3. Word Originmid 17th cent.: modern Latin, from Latin mille ‘thousand’, on the pattern of biennium.
See the Oxford Advanced American Dictionary entry: millennium