graph Noun A diagram displaying data; in particular one showing the relationship between two or more quantities, measurements or indicative numbers that may or may not have a specific mathematical formula relating them to each other.

graph Noun A diagram displaying data, in particular one showing the relationship between two or more variables; specifically, for a function f(x_1, x_2, \ldots, x_n), the set of all tuples (x_1, x_2, \ldots, x_n, f(x_1, x_2, \ldots, x_n)).

graph Noun An ordered pair (V,E), where V is a set of elements called "vertices" (or "nodes") and E is a set of pairs of elements of V, called "edges"; informally, a set of vertices together with a set edges that join these vertices.