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

“Few restaurants last 50 years, let alone 150,” The New York Times wrote about Tadich in 1999, the restaurant’s sesquicentennial year.

From New York Times

Upcoming “celebration nights” recognize Ireland and Israel, Filipino and Hispanic heritages, and the sesquicentennial of baseball in Japan.

From Washington Post

Davis began working for the park service in 1990 and received the National Park Service Southeast Region’s Employee of the Year award in 2012 for her efforts with the Civil War sesquicentennial.

From Washington Times

The school had planned a sesquicentennial celebration online on Monday to mark its Founders Day.

From Washington Times