What word describes the 250th anniversary of U.S. independence celebrated by America250?

Semiquincentennial describes the 250th anniversary of U.S. independence celebrated by America250.

The word combines Latin-derived elements meaning half of five hundred, or 250. It is the formal name used for the United States’ 2026 anniversary of the Declaration of Independence. America250 is the shorter branding associated with the national commemoration.

The term is less familiar than bicentennial, which means a 200th anniversary, or tricentennial, which means a 300th anniversary. Other alternatives have appeared in historical writing, including sestercentennial and quarter millennium, but semiquincentennial is the standard official term for this observance.

The anniversary date is July 4, 2026. It follows the bicentennial celebrated in 1976 and precedes the tricentennial expected in 2076. The milestone is therefore both a national birthday celebration and a marker in a sequence of long-term commemorations.