👉 In mathematics, a cordiality is a property of a graph that describes how its vertices are connected to each other. It can be defined as the number of edges (or equivalently, the number of spanning trees) in a complete bipartite graph formed by two subsets of the vertices. The term "cordialities" refers to the concept of cordiality in graph theory. Cordiality is used to describe whether a graph has a particular property or structure such as being connected,