James J. "Jumbo" Davis (September 5, 1861 – February 14, 1921) was a Major League Baseball third baseman. He played all or part of seven seasons in the majors, between 1884 and 1891, for the Brooklyn Gladiators, St. Louis Browns, Baltimore Orioles, Washington Statesmen, and two different Kansas City Cowboys teams, one in the Union Association and the other in the American Association.