audible - a play called by the quarterback at the line of scrimmage to change the play that was called in the huddle.
automatic - an audible
blitz - a defensive maneuver in which one or more defensive backs, which normally remain behind the line of scrimmage, instead charge into the opponents' backfield in an attempt to sack the quarterback.
dead ball - a ball which is not in play after one play has ended and before the next play begins.
coffin corner - the corner of the field of play. A punter, if he is close enough, will often attempt to kick the ball out of bounds close to the receiving team's goal line and pin them back near their own end zone.
crackback block - an illegal block delivered from the back by an offensive player who had left the area of close line play and then returned to it.
defensive back - a cornerback or safety on the defensive team; commonly defends against wide recievers on passing plays. Generally there are 4 defensive backs playing at a time.
defensive team the team that begins a play from scrimmage not in possession of the ball.
dime back - the second extra, or sixth total, defensive back. Named because a dime is worth more than a nickle.
down - one of a series of four plays in which the offensive team must advance at least 10 yards or lose possession.
draw play - a play in which the quarterback drops back as if to pass, then hands off to a running back.
drop kick - a kick in which the ball is allowed to hit the ground before it is kicked. It was effectively used as a method of kicking field goals in the early history of football, but unheard of today, although it is still legal.
eligible receivers - offensive players who may legally catch a forward pass.
goal posts - a set of two upright posts extending above a crossbar. The distance between uprights is 18-1/2 feet, and the top of the crossbar is 10 feet above the ground.
live ball - any ball that is in play, whether it is a player's possession or not. The ball is live during plays from scrimmage and free kicks, including kickoffs.
long snapper - a center who specializes in the long, accurate, snapss required for punts and field goal attempts.
loose ball - any ball that is in play and not in a player's possession. This includes a ball in flight during a lateral or forward pass.
pulling - a term used to describe an offensive lineman who, instead of blocking the player in front of him, steps back ("pulls") and moves down the line to block another player, usually in a "trap" or "sweep."
punt - a kick in which the ball is dropped and kicked before it reaches the ground.
punter - a kicker who specializes in punts as opposed to kickoffs or field goals.
red dog - a blitz.
reverse - an offensive. play in which a ballcarrier going toward one side of the field hands off to a teammate who is running in the opposite direction. (if the second ballcarrier is an end, it's an "end around")
running back
rush - trying to tackle or hurry a quarterback before he can throw a pass.
sack - tackling the quarterback before he can get off a pass.
strong side - the side of the field with the most offensive players on the line of scrimmage.
stunt - a tactic used by defensive linemen in which they switch sides in an attempt to get past the blockers.
T-formation - a classic offensive formation with the quarterback directly behind the center and two or three running backs behind the quarterback, forming a 'T'.
tackle - the act of forcing a ball carrier the ground
touchback - the act of downing the ball behind one's own goal line after the ball had been propelled over the goal by the opposing team. After a touchback, the team that downed it gets the ball at their own 20-yard line.
touchdown - a play worth six points, accomplished by gaining legal possession of the ball in the opponent's end zone.
trap - a basic blocking pattern in which a defensive lineman easily gets past the line of scrimmage, only to be blocked by a "pulling" lineman.