Glossary of American Football - D

D

dead ball
A ball which is no longer in play.
dead-ball foul
A penalty committed by either team before or after the play. If it is after, the result of the play stands and the penalty is assessed from the current position of the ball. Pre-snap penalties on the defense do not require the play to be blown dead unless a defensive player has a clear path to the quarterback. On the offense, some penalties do stop the play before it begins and some do not. A dead ball foul that does not stop play cannot be declined. A frequent dead ball foul is delay of game.
defensive back
A cornerback or safety position on the defensive team; commonly defends against wide receivers on passing plays. Generally there are 4 defensive backs playing at a time; but see nickel back and dime back.
defensive end (DE)
A player position on defense who lines up on the outside of the defensive line and which principal function is to deliver pressure to the Quarterback. Also known as Rush.
defensive tackle (DT)
A player position on defense on the inside of the defensive line and which principal function is to contain the run. When a defensive tackle lines up directly across from the center, he is known as a nose tackle, often the heaviest player on the defense. When a defensive tackle lines up between offensive guard OG and Offensive tackle OT, he is known as a 3-gap technique tackle.
defensive team
The team that begins a play from scrimmage not in possession of the ball.
delay of game
A foul which occurs when the offensive team does not put the ball in play before the play clock runs out. There are also less common occurrences which result in a delay of game foul, such as a defensive player holding an offensive player on the ground to prevent him from lining up during a two-minute drill. Penalty: 5 yards.
dime back
The second extra, or sixth total, defensive back. Named because a dime has the same value as two nickels. See nickel back.
direct snap
A play in which the ball is passed directly to the presumed ball carrier by the center. Contrast with an indirect snap play in which the ball is first handed to the quarterback, who will then pass or hand it to the eventual ball carrier. Also used to refer to formations that use a direct snap, such as the single wing.
dive
A play in which the ball is handed off to the running back, who attacks the middle of the offensive formation (between the OG). This play is part of the Triple option strategy.
double reverse
A play in which the ball reverses direction twice behind the line of scrimmage; this is usually accomplished by means of two or three hand-offs, each hand-off going in an opposite direction as the previous one. Such a play is extremely infrequent in football. Some people confuse the double reverse with a reverse, which is a play with two hand-offs instead of three.
double wing
A formation with 2 tight ends & 2 wingbacks in which the snap is tossed by the center between his legs to the quarterback or halfback moderately deep in the backfield.
double wing(ed)-T
A formation with 2 tight ends & 2 wingbacks in which the center hands the ball to the quarterback, who holds his hands between the legs of the center.
down
A unit of the game that starts with a legal snap or legal free kick after the ball is ready for play and ends when the ball next becomes dead. First down is the first of the plays; fourth is the last down in American (third in Canadian) football. A first down occurs after a change of possession of the ball, after advancing the ball 10 yards following a previous first down or after certain penalties.
down box
The post used with the chain gang to mark the line of scrimmage and designate the current down.
down by contact
When the player carrying the ball touches the ground with any part of his body other than his feet, hands, or arms as a direct result of contact with a player of the opposing team. In professional football a player must be down by contact in order for play to stop; if he trips and falls without being touched by an opposing player he is free to get up and continue advancing the ball. Exceptions to this rule that result in play stopping include when the player carrying the ball is on the ground but not downed by contact (e.g., after tripping and falling) and is touched by a member of the opposing team while still on the ground; or when the player with the ball intentionally kneels down or throws himself on the ground and stops advancing, e.g., a quarterback kneel or touchback. This rule does not apply in collegiate and high school football, i.e., a player need not be downed by contact at these levels in order for play to stop.
down lineman
A player stationed in front of his line of scrimmage and who has either one (three-point stance) or two (four-point stance) hands on the ground.
draw play
A play in which the quarterback drops back as if to pass, then hands off to a running back or runs with the ball himself. Contrast with scramble
drive
1. A continuous set of offensive plays gaining substantial yardage and several first downs, usually leading to a scoring opportunity.
2. A blocking technique - "drive block" - in which an offensive player through an advantaged angle or with assistance drive a defensive player out of position creating a hole for the ball carrier.
drop kick
A kick in which the ball is dropped and kicked once it hits the ground and before it hits it again; a half-volley kick. A drop kick is one of the types of kick which can score a field goal. Drop kicks are extremely rare due to the pointed nature of the ball.
dual-threat quarterback
A quarterback who is skilled at both passing and rushing the ball. These quarterbacks may be difficult to defend against since the defensive team cannot focus on one threat to the exclusion of the other.

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