University philosopher's employment (5)
I believe the answer is:
usage
'employment' is the definition.
(synonyms)
'university philosopher's' is the wordplay.
'university' becomes 'U' (abbreviation for university).
'philosopher' becomes 'sage' (sage can mean a wise person).
'u'+'sage'='USAGE'
(Other definitions for usage that I've seen before include "Acceptable language" , "etiquette" , "Treatment; tradition" , "Accepted or habitual practice" , "management" .)