"Subproperty of" is a declarative predefined property to define that a property is a subproperty of another and is provided by Semantic MediaWiki. This property is pre-deployed (also known as special property) and comes with additional administrative privileges but can be used just like any other user-defined property.
This is the page of special property Subproperty of. It lists all properties using this special property. See the help page Special property "Subproperty of" for further information.
