Same level within department (3)
I believe the answer is:
par
'same level' is the definition.
(par is an average or standard level)
'within department' is the wordplay.
'within' indicates a hidden word.
'PAR' can be found hidden inside 'department'.
(Other definitions for par that I've seen before include "Average score for good golf player" , "Usual score at golf" , "Rap to get even" , "Usual or expected level" , "Accepted level" .)