Authorise staff appointment (7)
I believe the answer is:
mandate
'authorise' is the definition.
(to mandate is to confer authority)
'staff appointment' is the wordplay.
'staff' becomes 'man' (as in staffing or manning a particular place).
'appointment' becomes 'date' (synonyms).
'man'+'date'='MANDATE'
(Other definitions for mandate that I've seen before include "directive" , "Social appointment for male - or authority given" , "Make compulsory" , "Authority conferred on a tandem" , "Legal authorisation" .)