n. pl. mil·len·ni·a (-lĕnē-ə) or mil·len·ni·ums 1. A span of one thousand years. 2. A thousand-year period of holiness mentioned in the book of Revelation, during which Jesus and his faithful followers are to rule on earth. 3. A hoped-for period of joy, serenity, prosperity, and justice. 4. A thousandth anniversary. [New Latin mīllennium : Latin mīlle, thousand; see gheslo- in the Appendix of Indo-European roots + Latin annus, year; see at- in the Appendix of Indo-European roots.] |
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