Flag pattern – The course that a wide receiver runs where he starts running straight downfield and then turns and runs diagonally toward the back corner of the end zone.

Flea Flicker – A trick play where the quarterback hands the ball off to the running back straight up the middle, but then the running back stops, and tosses the ball back to the quarterback behind him who then throws the ball deep downfield to a receiver.

Field position – The yard line that the ball is on. Many games are won because a team continually has better starting field position.

Flanker – A receiver who doesn’t line up on the line of scrimmage. May line up just a step behind the line or in the offensive backfield.

Flat – An area on the field outside the hashmarks and 0-10 yards forward of the line of scrimmage to the offense.

Not used very often, since it can also make his own linemen jump early and draw a false start penalty

Franchise tag – A ploy by an NFL team during negotiations with one of their own free agents. If a team puts the franchise tag on a player, that player is under contract for a period of one year at a salary equal to the average of the top five players at his position. Read More FG – The abbreviation for a field goal