What term beginning with “semi-” names America’s 250th anniversary?

The term beginning with “semi-” that names America’s 250th anniversary is semiquincentennial.

The word combines “semi,” meaning half, with “quincentennial,” relating to 500 years. A 250th anniversary is therefore half of a 500-year anniversary. The term is used for the United States’ 2026 commemoration and appears alongside the America250 branding.

Other anniversary terms can be easy to confuse. A bicentennial marks 200 years, a sesquicentennial marks 150 years, and a tricentennial marks 300 years. “Semiquincentennial” is less familiar in everyday speech, which is why America250 was promoted as a shorter public-facing name.

Alternative labels have appeared in historical and media discussions, including “bisesquicentennial” and “sestercentennial.” However, “United States Semiquincentennial” is the formal title used for the national 250th-anniversary observance.