Relationship as a primary constituent of reality setting a mutual order of things in the world commonly involves a large number of the terms or components or arguments that it interrelates. Realistic, actual, factual, existent, or real relationships consist of a multitude of elements, or parts, or terms, thus being polyadic, N-term connections. This implies that a true modeling of N-relational entities should consider their real nature, types, and properties (ontology) as well as the meanings of their correlatives (semantics) and formal attributes (mathematics). The first considers the reality of relations, telling us: • How they exist, intrinsically and inherently (in the very nature of things) or extrinsically and extraneously (as connections among things) • What kinds of relational species are there • How relationships are classified The second one indicates the primary meanings (definition or intension) with the connotative senses (extension) of the relations, or how they draw their meanings, from the correlative terms or from the relation itself. The third expresses the relationships in terms of mathematical sets, quantities, variables, functions, arguments, and values.