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A vocabulary is a set or collection of terms. It is a generic term to refer to sets of concepts that could be concretely described in an ontology, taxonomy, or thesaurus.

DescribesConcepts (content) and the relationships between them (structure), including axioms and restrictionsHierarchical relationships among concepts, and specifies the term to be used to refer to eachHierarchical and non-hierarchical relationships among conceptsGeneral term for a collection of concepts (words) to do with a domain
RelationshipsTyped hierarchical and associativeBasically hierarchical, but all modeled using same notationUntyped hierarchical, associative, and equivalenceUnspecified (abstract concept)
PropertiesRDFS defines relationship properties and restrictionsNoneCan be described in scope notes if requiredUnspecified (abstract concept)
StructuredNetworkTreeCross-branch treeUnspecified (abstract concept)

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