William Daniel MacLeod (May 13, 1942 – December 12, 2018) was an American relief pitcher in Major League Baseball who played briefly for the Boston Red Sox during the 1962 season. The Gloucester, Massachusetts, native threw and batted left-handed and was listed as 6 feet 2 inches (1.88 m) tall and 190 pounds (86 kg). In his two relief appearances, MacLeod posted a 0–1 record with two strikeouts, one walk, four hits allowed, and a 5.40 ERA in 12⁄3 innings pitched.