What term means the 250th anniversary celebrated by America250?

The term semiquincentennial means the 250th anniversary celebrated by America250.

The word is built from “semi,” meaning half, and “quincentennial,” relating to 500 years. Half of 500 is 250, so a semiquincentennial is a 250-year anniversary. The term is unusual because everyday speech more often uses “250th anniversary.”

America250 applies the term to the national observance of the 250th anniversary of the Declaration of Independence. Other names found in historical and reference sources include sestercentennial, bisesquicentennial, and quarter millennium.

The related terms are numerical markers: a centennial is 100 years, a sesquicentennial is 150, a bicentennial is 200, and a tricentennial is 300. Knowing those distinctions prevents confusing the 2026 celebration with the 1976 Bicentennial.