What it is

The front seven is the group of defenders closest to the line of scrimmage: the linemen and linebackers, usually seven players.

In a game

They are responsible for stopping the run and rushing the passer. The other four defenders, the defensive backs, form the secondary.

More detail

The word “seven” fits a 4-3 defense (four linemen, three linebackers), but a 3-4 defense also has seven players in the front. Coaches talk about a team’s “front” when they describe how the linemen are lined up.