William John "Bullfrog" Dietrich (March 29, 1910 – June 20, 1978) was an American professional baseball pitcher.

He played in Major League Baseball (MLB) from 1933 to 1948 for the Philadelphia Athletics, Washington Senators, and Chicago White Sox.

His Pennsylvania-born parents of German ancestry were Charles, an accountant, and Berth (Hopes) Dietrich.

[3] On June 1, 1937, while with the White Sox, Dietrich no-hit the St. Louis Browns 8–0 at Comiskey Park.

[4][5] In the film A Christmas Story, Mr. Parker says that "the Sox traded Bullfrog" for a player named "Schottenhoffen".