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lustrum

noun lus·trum \ ˈlə-strəm \

Definition of lustrum

plural lustrums or lustra play \ˈlə-strə\

1 : a period of five years

2 a : a purification of the whole Roman people made in ancient times after the census every five years

b : the Roman census

Origin and Etymology of lustrum

Latin

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First Known Use: 1590

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