Ability to add extra hierarchy levels (not just department)

We have had to create a logbook to record the extra layers of hierarchy within the company so that we can filter reports and share data with different managers. There is currently only Department within the system, the analytics tool often uses Department to filter or create clusters of data but it would be good to drill down to extra layers. It would also be fantastic if we could change the label "Department" to something else! e.g. Here is a possible Hierarchy:- Directorate, department, function, team, sub-team.