Convex Hull:

The convex hull of a set is the smallest convex set containing it. Alternatively, it is the intersection of all the convex sets containing it.

For example, the convex hull of three points in space is the planar triangle that has the three points as its vertices. The convex hull of a the unit circle in he plane is the unit disk, and the convex hull of a cube in space is the solid cube.

See also:

Convex Set

Convex Envelope

8/12/94 dpvc@geom.umn.edu -- The Geometry Center