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Table 1 Syntax and semantics of EL++ DL

From: SNOMED CT standard ontology based on the ontology for general medical science

Name OWL syntax Syntax Semantics
Top Thing I
Bottom Nothing
Atomic class Class C CI
Primitive role Object and data property R RI
Existential quantification ObjectSomeValuesFrom R. C {x I| y I : (x, y)  R  y  CI}
General class inclusion SubClassOf C  D CI DI
Role inclusion SubObjectPropertyOf R  S {x, y I| (x, y)  RI → (x, y)  SI}
Class equivalence EquivalentTo C ≡ D (C  D, D  C ) CI = DI
Conjunction ObjectIntersectionOf C  D CI ∩ DI
Domain restriction ObjectPropertyDomain R.     C {x I| (x, y)  RI}  CI}
Range restriction ObjectPropertyRange    R. C {y I| (x, y)  RI}  CI}
Disjointedness DisjointWith C  D  CI ∩ DI =