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

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

But Bacevich offers nothing from Calvin Coolidge’s luminous address on the sesquicentennial of the Declaration of Independence.

From New York Times • Apr. 1, 2020

By 2009, at the sesquicentennial, the country had seemingly changed, with Barack Obama its first African American president.

From Washington Post • Oct. 13, 2019

In the fall of that year minor repairs were made to the locomotive so that it might be used in the sesquicentennial celebration at Carlisle, Pennsylvania.

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.