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quadricentennial

American  
[kwod-ruh-sen-ten-ee-uhl] / ˌkwɒd rə sɛnˈtɛn i əl /

adjective

  1. of, relating to, or marking the completion of a period of four hundred years.

noun

  1. a quadricentennial anniversary.

  2. its celebration.

quadricentennial British  
/ ˌkwɒdrɪsɛnˈtɛnɪəl /

noun

  1. a 400th anniversary

"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

adjective

  1. of, relating to, or celebrating a 400th anniversary

"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

Etymology

Origin of quadricentennial

First recorded in 1880–85; quadri- + centennial

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.