William Oliver Gilbert (June 21, 1876 – August 8, 1927) was an American professional baseball second baseman who played from the 1890s through 1912. Gilbert played in Major League Baseball from 1901 to 1909, for the Milwaukee Brewers, Baltimore Orioles, New York Giants, and St. Louis Cardinals. Standing at just 5 feet 4 inches (1.63 m), Gilbert was a weak hitter but a good defensive second baseman. He did hit .313 in the 1905 World Series, which the Giants won.