The professional championship for major league baseball, played at the end of the season between the champions of the American League and the National League. It was first played in 1903.
Definition of World Series in US English:
World Series
proper nounwərld ˈsirēzwərld ˈsɪriz
The professional championship for North American major league baseball, played at the end of the season between the champions of the American League and the National League. It was first played in 1903.