William Leopold "Bill" Hoffer (November 8, 1870 – July 21, 1959) was a professional baseball player. He was a right-handed pitcher over parts of six seasons (1895–1899, 1901) with the Baltimore Orioles, Pittsburgh Pirates and Cleveland Blues. For his career, he compiled a 92–46 record in 161 appearances, with a 3.75 earned run average and 314 strikeouts. In 1901 he archived the dubious honor of being the losing pitcher in the American League's first game.
In his rookie year, 1895, he compiled 31 wins (including a league-leading four shutouts), a major league record for most wins as a rookie. He led the National League in Winning Percentage in 1895 and 1896.
He was born and later died in Cedar Rapids, Iowa, at the age of 88.