NCI Thesaurus Concept

**Semantic type:** Conceptual Entity

**Definition:** A concept is the basic unit of information contained in the Thesaurus. They describe sets of individuals in a given domain. A concept has a name, belongs to a Namespace and exists in relation to other concepts. The vertical relationships consist of "isa" statements that form a logical hierarchy (taxonomy or subsumption graph). In general, concepts above a given concept are referred to as superconcepts or parents and those below as subconcepts or children. In addition, there are horizontal named realationships between concepts called Roles, binary relations between concepts that provide a machine-interpretable definition of a concept and the means for discrimination of sibling concepts. A concept may also include Properties, named slots that allow attachment of external information to concepts.

**Synonyms:** - Concept - Terminology Concept