Main Entry: mil·len·ni·um

Pronunciation: \mə-ˈle-nē-əm\

Function: noun

Inflected Form(s): plural -nia \-nē-ə\ or mil·len·niums

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

Date: circa 1638

1 a : the thousand years mentioned in Revelation 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