A pass route on offense in which the offensive player runs straight down the field for a short while before cutting directly towards the nearest sideline. This route has the advantage that it takes the receiver towards the sideline, allowing him to get out of bounds after a catch. This makes the square out the most useful route in time management situations. Ideally, the route will force the defensive back away from the receiver before the turn is made, giving the quarterback a window to complete the pass through.
The square out is a staple route in most passing offenses. A good quarterback will put the ball on the outside of the receiver to lessen the risk of a turnover, believing that the pass will either be completed or go harmlessly out of bounds. The route is incredibly useful late in each half if a team is out of time-outs, because a receiver can gain yards before getting out of bounds to stop the clock. The major risk is if the ball is thrown behind the receiver, because a capable defensive back will jump the out route and have the possibility of returning an interception for a touchdown. A good receiver has to sell the downfield route to force the defensive back to retreat to avoid the possibility of a deep throw before he turns to the outside.