baseball (n.)
in the modern sense of a game of ball for teams of nine, 1845, American English, from base (n.) + ball (n.1). Earlier references, such as in Jane Austen's "Northanger Abbey," refer to the game of rounders, of which baseball is a more elaborate variety. The modern game was legendarily invented 1839 by Abner Doubleday in Cooperstown, N.Y. Base was used for "start or finish line of a race" from 1690s; and the sense of "safe spot" found in modern children's game of tag can be traced to 15c. (the use in reference to the bags in modern baseball is from 1868).