An edge or line marking an edge of the playing field.
The bounds, confines, or limits between immaterial things (such as one’s comfort zone, privacy, or professional sphere and the realm beyond).
The dividing line or location between two areas.
An event whereby the ball is struck and either touches or passes over a boundary (with or without bouncing), usually resulting in an award of 4 (four) or 6 (six) runs respectively for the batting team.
(of a set) The set of points in the closure of a set S, not belonging to the interior of that set.