Possible Definitions:
1. Vertical (a.) Of or pertaining to the vertex; situated at the vertex, or highest point; directly overhead, or in the zenith; perpendicularly above one.
2. Vertical (a.) Perpendicular to the plane of the horizon; upright; plumb; as, a vertical line.
3. Vertical (n.) Vertical position; zenith.
4. Vertical (n.) A vertical line, plane, or circle.
