D
- Decision - a point in an Activity diagram where a Flow splits into several, mutually exclusive, Guarded flows. A Merge marks the end of the optional behaviour started by the Decision
- Dependency - a dependency exists between two defined elements if a change to the definition of one would result in a change to the other. In UML this is indicated by a line pointing from the dependent to the independent element.
- Deployment diagram
- Derived property - a property that can be calculated or inferred from other properties
- Diagram - a visual representation of a subset of features of a UML Model
- Directed relationship -
- Domain - a logical grouping that explicitly declares a rule which defines ownership of objects based upon some type or property.
Read more about this topic: Glossary Of Unified Modeling Language Terms