Threevertex
Threevertex is a term encountered in several disciplines, generally denoting a vertex tied to three elements or forming part of a triadic structure. It is not a single standardized definition; its precise meaning depends on context.
In graph theory, a three-vertex (also called a tri-valent or cubic vertex) is a vertex of degree
In computational geometry and computer graphics, three vertices determine a triangle, the simplest polygon in the
Usage notes: some authors may use “3-vertex” or “three-vertex” interchangeably with degree-three vertex; others reserve it