Office temp's initial depression (4)
I believe the answer is:
dent
'depression' is the definition.
('dent' can be a synonym of 'depression')
'office temp's initial' is the wordplay.
'office' becomes 'den' (I've seen this before).
'initial' says to take the initial letters.
The initial letter of 'temp' is 't'.
'den'+'t'='DENT'
(Other definitions for dent that I've seen before include "Hollow from impact" , "Arthur, described by Douglas" , "tooth (13) [FRENCH]" , "Hollow caused by a blow" , "Tend to small indentation" .)