Dictionary
run•back
Pronunciation: (run'bak"), [key]—
n.
1. Football.
a. a run made by a player toward the goal line of the opponents after receiving a kick, intercepting a pass, or recovering an opponent's fumble.
b. the distance covered in making such a run.
2. Tennis.the space on a tennis court between the base line and the backstop.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.