A concept is sufficiently defined if its defining characteristics are adequate to define it relative to its immediate supertypes. A sufficiently defined concept is defined in the context of its hierarchy. See main glossary entry for sufficient definition.
A concept which is not sufficiently defined is primitive. A primitive concept is a formal logic definition that is inadequate to distinguish it from similar concepts. A primitive concept does not have enough defining relationships to computably distinguish it from more general concepts (supertypes).