Definition of Vertex

Vertex

1. A turning point; the principal or highest point; top; summit; crown; apex.
2. The top, or crown, of the head.
3. The zenith, or the point of the heavens directly overhead.
4. The point in any figure opposite to, and farthest from, the base; the terminating point of some particular line or lines in a figure or a curve; the top, or the point opposite the base.