A quarterback who makes the majority of his passes from within the passing pocket.
The passing pocket, also known as the tackle box, is a space in the backfield formed by offensive linemen who create a wall of protection that provides the quarterback with adequate time to execute a pass play. A pocket passer is a quarterback who is usually highly skilled at standing tall and passing the football from within the pocket, as opposed to a more mobile quarterback who relies on bootleg or option plays. Although pocket passers are typically viewed as more cerebral and less athletic, the term is often attributed to more experienced quarterbacks who can perform subtle movements and step up in the pocket to avoid pressure.
Examples of pocket passers are Peyton Manning, Tom Brady and Drew Brees.