William James "Buster" Hoover (April 12, 1863 – April 16, 1924) was an American outfielder in Major League Baseball. He played for the Philadelphia Keystones, Philadelphia Quakers, Baltimore Orioles, and Cincinnati Reds between 1884 and 1892. Described as a "long legged heavy hitter", Hoover was among his league's leaders in several offensive statistics during his 12-year professional baseball career. In 127 career major league games, Hoover had a batting average of .288. He stood 6 feet 1 inch (1.85 m) and weighed 178 pounds (81 kg).