Source (a hypercube) contains the target (a dimension) among others. definitionArc Source (a dimension) has only the target (a domain) as its domain. definitionArc Source (a domain) contains the target (a member). definitionArc Source (a primary item declaration) requires a combination of dimension members of the target (hypercube) to appear in the context of the primary item. definitionArc Source (a primary item declaration) requires a combination of dimension members of the target (hypercube) not to appear in the context of the primary item. definitionArc Source (a dimension) declares that there is a default member that is the target of the arc (a member). definitionArc