Note that many of the Oracle Applications products (and their documentation) do not necessarily refer to key flexfield combinations as "combinations". They may refer to combinations using the name of the entity or the key flexfield itself. For example, Oracle Assets uses a key flexfield called the "Asset Key Flexfield" and refers to one of its combinations as "an asset key" or "an asset key flexfield". In another example, Oracle General Ledger and other Oracle Applications products generally use the term "account" or "GL account" to refer to combinations of the Accounting Flexfield.
Planning your Key Flexfield
Key Flexfield Structure Planning Diagram