2-Point Conversion:  When a team that just scored a touchdown starts a play at the opponent’s 2-yard . . .
3-3-5 Defense:  A variation of the Nickel formation with 3 linemen (2 De & 1 DT), 3 linebackers . . .
3-4 Defense:  A defensive formation with 3 linemen and 4 linebackers. A professional derivativ . . .
4-3 Defense:  A defensive formation with 4 linemen and 3 linebackers. Several variations are e . . .
4-4-4 Defense:  Illegal participation (name so derived from the fact that 4+4+4=12 men on the fi . . .
46 Defense:  (pronounced forty-six defense) a formation of the 4-3 defense (four linemen and . . .
50 Defense:  A once popular college defense with 5 defensive linemen and 2 linebackers. Also . . .
A-11 Offense:  An offensive philosophy designed to appear as if all 11 players are eligible rec . . .
Air Raid:  An offensive philosophy derived from the West Coast Offense but adapted to the s . . .
Air Yards:  The yards gained by a pass through the air. It is the distance gained by a pass . . .
All-Purpose Yardage:  The sum of all yards gained by a player who is in possession of the ball during . . .
Astroturf:  An artificial surface used instead of grass on many football fields. . . .
Audible:  A play called by the quarterback at the line of scrimmage to make a change from . . .
Automatic First Down:  For several of the most severe fouls against the defensive team, a first down is . . .
Back:  A position behind the offensive and defensive linemen. Offensively, mostly used . . .
Backfield:  The area behind the line of scrimmage.
Backs:  The running backs; the halfback and the fullback.
Backup:  A second string player who does not start the game, but comes in later in relief . . .
Backward Pass:  A pass thrown to the side or backward. Also called 'onside pass' in Canadian foo . . .
Ball Carrier:  Any player who has possession of the ball.