Display labels in 360 feedback allows you to change the reviewer type labels (Self, Supervisor, Direct Report, Peers, External Reviewer) in the application as well as in the email you get to review an employee. For example, you can change "Supervisor" to "Manager" in the application and at the same time change "Supervisor" to "Head" in the email that a user would get to review an employee.
To change display labels, go to:
Login >> Workforce >> 360 feedback survey