Canadian Football – Canada’s version of football is very similar to the NFL but has a few minor rule variations such as a longer field

Carry – running with the ball, see “Rush”

Center – the offensive lineman in charge of “Snapping” the ball to the “Quarterback”

CFL – the Canadian Football League; see “Canadian Football”

Chain Gang -- assistants to the “Officials” in charge of moving the chains

Chains – the measurement implements used by “Officials” to mark the position of the ball 

Cheap Shot  -- intentionally fouling an unsuspecting player  

Cheat Sheet – a tool used by fantasy football players in the draft, usually ranking available players

Check Off – See “Audible”

Chop Block – An aggressive block beneath the knees

Clipping – An illegal block from behind, generally in the lower legs

Clothesline – hitting an opponent in the neck or the face, an illegal maneuver resulting in a 15 yard penalty

Coffin Corner – the corners of the field between the five yard line and the goal line, often where the “Punter” tries to place the ball 

Coin Toss – a coin flipped by an official at the start of the game to determine who has possession of the ball. The visiting team calls the result; the winner of the coin toss gets to decide whether to “Kick-off” or receive the ball
 
Completion – a successful forward pass; in the “NCAA,” a “Receiver” must have possession for one step before going out of bounds; in the “NFL” the receiver must take two steps  

Conferences – a system of dividing both the “NCAA” and “NFL” teams for playoff and scheduling purposes; the NFL has two conferences, the NCAA has several 

Controlling the Clock – a playing strategy that involves maintaining possession of the ball for extended periods of time to reduce the opposing team’s scoring opportunities; usually involves a lot of running plays

Cornerback – a defensive player who usually lines up against the “Wide Receiver” for coverage on pass plays

Count – signals the quarterback calls out before the ball is snapped

Counter – an offensive play designed to misdirect the defense by faking a move in one direction before carrying the ball the other direction

Cover – following an offensive player across the field in order to prevent him from catching a pass or scoring

Coverage – defensive strategy intended to prevent the offense from gaining yardage or scoring 

Crackback Block – an illegal move in which an offensive player who is positioned at least two yards outside the “Offensive Tackle” blocks an opponent below the waist when the defender is headed toward the location from which the ball was snapped and within five yards of the line of scrimmage

Curl – a pass route in which the wide receiver runs toward the goal, then turns back toward the scrimmage line

Cut – a sudden change in direction when running (also known as a “cutback”), or to be dropped from a team’s roster