semiquincentennial

American  

[sem-ee-kwin-sen-ten-ee-uhl, sem-ahy-] / ˌsɛm iˌkwɪn sɛnˈtɛn i əl, ˌsɛm aɪ- /

noun

1. a 250th anniversary or its celebration.

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adjective

1. relating to a 250th anniversary or its celebration.

2. lasting or having lasted 250 years; 250 years old.

Explanation

Semiquincentennial is a very long word for a very big anniversary — 2026 is the semiquincentennial, or 250th anniversary, of the United States. Semiquincentennial derives from the Latin words semi, "half," quinque, "five," and centum, "one hundred." You don't need this word very often, since it's rare that a country, building, or organization marks its 250th anniversary, but when you do, it's a big deal. The British Parliament celebrated its semiquincentennial in 1957, and the Taj Mahal was built in 1648, which means its semiquincentennial happened back in 1898.

Example Sentences

See Examples For:

semiquincentennial

This series is designed “to inspire and motivate Americans” to travel during the country’s semiquincentennial celebration, never mind the astronomical gas prices.

From Los Angeles Times ● Aug. 21, 2026

America’s blowout Fourth of July wasn’t the only semiquincentennial of 2026.

From The Wall Street Journal ● Aug. 21, 2026

But her relationship to America’s founding, particularly this year’s semiquincentennial, is far from usual.

From Salon ● Jul. 27, 2026

Freedom 250 is a Trump administration initiative to promote the country’s semiquincentennial.

From MarketWatch ● Jul. 6, 2026

Two-and-a-half centuries after adopting the Declaration of Independence, America is marking its semiquincentennial with a coast-to-coast spectacle.

From The Wall Street Journal ● Jul. 4, 2026