[ luhs-truh m ]
/ ˈlʌs trəm /

noun, plural lus·trums, lus·tra [luhs-truh] /ˈlʌs trə/.

Also luster; especially British, lustre. a period of five years.
Roman History. a lustration or ceremonial purification of the people, performed every five years, after the taking of the census.

Origin of lustrum

1580–90; < Latin lūstrum; cf. luster1 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for lustrum

British Dictionary definitions for lustrum



/ (ˈlʌstrəm) /

noun plural -trums or -tra (-trə)

a period of five years

Word Origin for lustrum

C16: from Latin: ceremony of purification, from lustrāre to brighten, purify
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for lustrum



(plural lustra), "purification of the Roman people every five years," 1580s, from Latin lustrum, perhaps from root of luere "to wash," related to lavere (see lave). Or [Watkins, Klein] from PIE *leuk-stro-, from base *leuk- "light, brightness."

Online Etymology Dictionary, © 2010 Douglas Harper