What term describes the 250th anniversary that America250 will mark for the United States?

The 250th anniversary that America250 will mark for the United States is called a semiquincentennial.

The word combines Latin-derived elements meaning half and five hundred, producing the sense of half of 500 years. In anniversary vocabulary, a semiquincentennial is therefore a 250-year observance. The United States reaches that milestone in 2026, counting from the 1776 Declaration of Independence.

The term is less familiar than bicentennial, which means 200 years, and centennial, which means 100 years. Sesquicentennial means 150 years, so it describes a different anniversary altogether. These similar-sounding labels are a frequent source of confusion in historical writing.

America250 is the branding used for the United States Semiquincentennial. The commemoration connects the 2026 national anniversary with museums, historic sites, schools, civic groups, and public events that explore the country’s history and continuing development.