The defense, by definition, cannot be called offside. This is because the offside position is measured from the moment a teammate last plays the ball. If the ball is in clear possession of the other team, you cannot be called offside.
This penalty is called "Clipping".
There is no penalty for that
Football as in soccer is called voetbal Football as in American Football is called American Football
Offense-Holding/False Start Defense- Pass Interference/Offside
If there is an offside infraction, the assistant referee (sometimes called Linesman) will raise his flag to indicate that play must be stopped, and follow the the appropriate signal. Play will be restarted with an indirect free kick to the defenders from the location where the offside player was at the moment that his teammate played it.
It is called the penalty arc. It is to ensure that defenders are 10 yards from the penalty spot when a penalty kick is taken.
When one player is off his side and on the opponet's side before the snap. when a defensive player crosses the line of scrimmage before the snap, also called encroachment. if an offensive lineman moves at all before the snap it is false start.
Its called Offside, or being in an offside position. Being in an offside position, in and of itself, is not a foul. The foul occurs when the ball is PLAYED to the PERSON in an offside position. You can be "passive", not involved in the play, in an offside position and there is no foul.
The penalty box
Football/Soccer is called football and NFL would be called American football.
There is no restart called an offside kick. The method of restarting play after an offside offense is an indirect free kick for the opposing team.