What term describes the United States’ 250th anniversary, commemorated by the America250 program?

The United States’ 250th anniversary is called the United States Semiquincentennial.

The word “semiquincentennial” combines “semi,” meaning half, with “quincentennial,” meaning a 500th anniversary. Half of 500 is 250, making the term a precise description of the anniversary. The celebration is also widely branded as America250.

The anniversary marks 250 years since the Second Continental Congress adopted the Declaration of Independence in 1776. National observances are scheduled throughout 2026, with the central anniversary falling on July 4. The semiquincentennial commemorates the nation’s founding while also presenting programs about the broader history of the United States.

A common mix-up is “bicentennial,” which refers to a 200th anniversary and described the major 1976 celebrations. “Sesquicentennial” means 150 years, while “tricentennial” means 300 years. “Quasquicentennial” means 125 years, so it is not another name for the 250th anniversary.