1) Football player 2) Footballer 3) Gridiron position 1) Passstealer 
A cornerback (CB) (also referred to as a corner) is a member of the defensive backfield or secondary in American and Canadian football. Cornerbacks cover receivers, to defend against pass offenses and make tackles. Other members of the defensive backfield include the safeties and occasionally linebackers. The cornerback position requires speed and...
A defensive player who is aligned at the edge or corner of the field, and who is assigned to cover the wide receiver of the offensive team. Cornerbacks must be quick and athletic.
(from the article `football, gridiron`) The original defenses had simply mirrored the positions of the offense. In the 1930s a 6-2-2-1 alignment became dominant (6 linemen, 2 linebackers, 2 ...
a defensive back who lines up near the line of scrimmage across from a wide receiver. Their primary job is to disrupt passing routes and to defend against short and medium passes.
A defensive position on scrimmages. Typical formations include two cornerbacks, whose main duty is to cover wide receivers. See also defensive back.
noun a defensive football player stationed outside the linebackers
one of two defensive backs positioned in the secondary between the linebackers and safeties, responsible for covering the outside areas near the sidelines against end runs and pass plays.