Every American football team has its own vocabulary for referring to different defensive positions. Here are some of the most common terms that teams use to refer to defensive linemen and their alignments:
Under tackle: A defensive tackle who lines up outside the offensive guard to the split end side. The entire defensive line aligns under (or inside) the tight end to the split end side. The under tackles possess strength and exceptional quickness off the ball, but they aren’t powerful players.
Open end: A defensive end who lines up to the split end or open end side of the formation — away from the tight end side. (If the offensive formation has two tight ends, there’s no open side and therefore no open end.)
Coaches generally put their best pass-rusher at the open end position for two reasons:
He has the athletic ability to match up with the offensive tackle.
If he’s positioned wide enough, a running back may be forced to attempt to block him, which would be a mismatch.
Elephant end: The elephant end lines up on the tight end side of the offense, and then attempts to disrupt the tight end’s release (his desire to escape the line of scrimmage and run down the field) on each play. This position gives the defense an advantage because the tight end generally has trouble blocking this talented defensive end.
Pass-rushing end: A player on the defense who has superior skills at combating offensive linemen and pressuring the quarterback. These ends can line up on either side of the defensive line.
His primary job is to get the best possible pass-rush, although he reacts to the run if a pass play doesn’t develop. If the quarterback is in a shotgun formation, the pass-rushing end must focus on where he expects the quarterback to be when he attempts to throw his pass.