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quatercentenary

[kwot-er-sen-ten-uh-ree, -sen-tn-er-ee; especially British kwot-er-sen-tee-nuh-ree]
noun, plural quat·er·cen·ten·ar·ies.
  1. a 400th aniversary or its celebration.
adjective
  1. pertaining to or marking a period of 400 years; quatercentennial.

Origin of quatercentenary

1880–85; < Latin quater four times + centenary
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for quatercentenary

quatercentenary

noun plural -naries
  1. a 400th anniversary or the year or celebration marking it
Derived Formsquatercentennial (ˌkwætəsɛnˈtɛnɪəl), adjective, noun

Word Origin for quatercentenary

C19: from Latin quater four times + centenary
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