Nomen is defined as an entity in the official RDA. An appellation relationship exists between an RDA entity and a nomen, for example, corporate body "has appellation" nomen. Appellations can be a name (e.g., preferred name of RDA entity), access point (e.g., authorized access point for RDA entity), or identifier.

LRM defined two subclasses for the entity agent (person and collective agent). The official RDA defined two subclasses of the entity collective agent to include family and corporate body.

Like the original RDA, two types of access points are defined in the official RDA: the authorized access point and the variant access point. These access points can be constructed using the preferred nomen for an entity (e.g., an instance of the entity person) with the possible addition of other data (for example the person's dates of birth and death) if necessary for identification and differentiation from other persons with similar preferred names.