sesquicentennial

American  

[ses-kwi-sen-ten-ee-uhl] / ˌsɛs kwɪ sɛnˈtɛn i əl /

adjective

1. pertaining to or marking the completion of a period of 150 years.

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noun

1. a 150th anniversary or its celebration.

sesquicentennial British  

/ ˌsɛskwɪsɛnˈtɛnɪəl /

adjective

1. of or relating to a period of 150 years

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noun

1. a period or cycle of 150 years

2. a 150th anniversary or its celebration

Other Word Forms

• sesquicentennially
  adverb

Etymology

Origin of sesquicentennial

An Americanism dating back to 1875–80; sesqui- + centennial

Example Sentences

See Examples For:

sesquicentennial

The fight for women’s suffrage, the prohibition movement and other progressive achievements marked the years before the sesquicentennial.

From The Wall Street Journal ● May 22, 2026

It’s the sesquicentennial of Western Australia, and everyone on Tony and Judy’s cul de sac is excited.

From Los Angeles Times ● Oct. 2, 2024

You could see this at the Sievierodonetsk library, where last year they celebrated the sesquicentennial of Lesya Ukrainka, Ukraine’s great modernist poet and playwright.

From Seattle Times ● Dec. 28, 2022

You know the rest: Days before the show’s planned opening, the coronavirus pandemic forced this museum and every other in New York to shut down, and turned the Met’s sesquicentennial into an annus horribilis.

From New York Times ● Aug. 27, 2020

It was on the engine at the time of the Carlisle sesquicentennial but disappeared by the time of the St. Louis exposition.

From The 'Pioneer': Light Passenger Locomotive of 1851 United States Bulletin 240, Contributions from the Museum of History and Technology, paper 42, 1964 by White, John H.