Source : Webster's Revised Unabridged Dictionary (1913)

Shortstop \Short"stop`\, n. (Baseball)
   The player stationed in the field bewtween the second and
   third bases.

Source : WordNet®

shortstop
     n 1: (baseball) the person who plays the shortstop position
     2: the fielding position of the player on a baseball team who
        is stationed between 2nd and 3rd base [syn: {short}]