What do the terms semiquincentennial, bisesquicentennial, sestercentennial, and quarter millennium have in common? They are all very long words used to describe a very big anniversary. Why are there so many names for America’s 250th birthday? Mainly because it’s such a rare achievement that it lacks a simple, easy-to-pronounce English word for it. As a result, language experts and historians use a combination of Latin roots to fully convey its meaning.

Quarter millennium is probably the easiest to understand because 250 is one-fourth of a millennium, or 1,000 years. Still, some prefer the term sestercentennial, which combines the Latin word sesterce (meaning two-and-a-half units) with centum (meaning hundred). Still others like the word bisesquicentennial, which adds 100 years to the term “150 years sesquicentennial.”

The America250 Commission, a nonpartisan organization tasked with commemorating the generational milestone, had adopted the term semiquincentennial for the occasion, which is a combination of three Latin words meaning half of 500 years. While it’s not a word that one uses every day, when you do, it’s a big deal. However, the seven-syllable name is a mouthful, which is why you will see variations of “America 250” on T-shirts, coins, stamps, and other commemorative memorabilia. 

No matter which term you prefer, America’s 250th birthday on July 4, 2026, will be a momentous event that will inspire a wave of patriotism at the local, state, and national levels. As the “Crossroads of America,” Indiana was known as the original western frontier and has made significant contributions to the country over the past 250 years. The semiquincentennial encourages all Hoosiers to take part in the celebration honoring the world’s oldest continually existing constitutional republic, as well as the positive impact Indiana has had on the nation’s history.