The slant route in football is a running route in which the running back runs diagonally in a 45-degree angle after getting the handoff from the quarterback, instead of in a straight line. For a slant run to work well it is necessary for the running back to have a lot of speed and agility. The change of motion to run diagonally must be made suddenly, confusing the defense, and creating leverage against any other players who may be trying to sack the ball carrier.
The slant run is similar to the slant passing pattern, where the receivers make a sudden change of direction after catching a pass from the quarterback, whereas in the run the running back executes the same move after a handoff from the quarterback. In a slant run, the running back must run diagonally, but not close enough to the sideline so that he is easily pushed out of bounds. That is especially true around the line of scrimmage, where there are many defensive players.