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English definition of “millennium”


noun [C]  /məˈlen·i·əm/ (plural millennia  /məˈlen·i·ə/ or millenniums) us  
a period of 1000 years: The area has experienced the worst drought in half a millennium.
adjective [not gradable]  /məˈlen·i·əl/ us  
(Definition of millennium from the Cambridge Academic Content Dictionary © Cambridge University Press)
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