vertex

Etymology

Late Middle English, borrowed from Latin vertex (“whirl, eddy; top, crown, peak, summit”). Doublet of vortex.

noun

1. The highest point, top or apex of something.
   1. (anatomy) The highest surface on the skull; the crown of the head.
2. (geometry) An angular point of a polygon, polyhedron or higher order polytope.
   1. The common point of the two rays that form an angle.
   2. The point at which an axis meets a curve or surface.
3. (mathematics) A point on the curve with a local minimum or maximum of curvature.
4. (graph theory) One of the elements of a graph joined or not by edges to other vertices.
   Coordinate term: plot
5. (computer graphics) A point in 3D space, usually given in terms of its Cartesian coordinates.
6. (optics) The point where the surface of a lens crosses the optical axis.
7. (particle physics) An interaction point.
8. (astrology) The point where the prime vertical meets the ecliptic in the western hemisphere of a natal chart.
9. (typography) A sharp downward point opposite a crotch, as in the letters "V" and "W" but not "Y".
   Coordinate term: apex