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quasquicentennial

American  
[kwos-kwi-sen-ten-ee-uhl] / ˌkwɒs kwɪ sɛnˈtɛn i əl /

adjective

  1. pertaining to or marking a period of 125 years.

noun

  1. a 125th anniversary.

  2. a celebration marking such an anniversary.

Etymology

Origin of quasquicentennial

quasqui- “one and a quarter” ( pseudo-Latin, apparently qua(dri-) + (se)squi- ) + centennial ( def. )

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.