A term used by Oracle Analytical Workspace:
Each level represents a position in the hierarchy. For example, a time dimension might have a hierarchy that represents data at the month, quarter, and year levels.
Each level above the base (or most detailed) level contains aggregate values for the levels below it. The members at different levels have a one-to-many parent-child relation. For example,
Q2-05 are the children of
2005 is the parent of
Hierarchies and levels have a many-to-many relationship. A hierarchy typically contains several levels, and a single level can be included in more than one hierarchy.