It is a chart with the list of all the accounts (Funds, Objectives, Responsibilities & Items) that are used in the department.
It is the combination of the Fund + Objective + Responsibility and the Item at a posting level.
It is a link between the Fund, Objective and the Item, that has been set-up to validate the allocations.
It is the term used in BAS to identify the different components of the accounting structure used in Government.