D defs.my
Entry 1 sense Webster, 1913

Millennial

/mĭl-ĕn'-ē-əl/ · Mil·len·ni·al · IPA /məˈlɛ.ni.əl/
01 a. Of or pertaining to the millennium, or to a thousand years; as, a millennial period; millennial happiness.
  1. 1.
    Of or pertaining to the millennium, or to a thousand years; as, a millennial period; millennial happiness.