Court official, man after gratuity (8)
I believe the answer is:
tipstaff
'court official' is the definition.
(I've seen this before)
'man after gratuity' is the wordplay.
'man' becomes 'staff' (both can mean to work at a particular post).
'after' says to put letters next to each other.
'gratuity' becomes 'tip' (synonyms).
'staff' after 'tip' is 'TIPSTAFF'.
(Other definitions for tipstaff that I've seen before include "Bailiff" , "Old officer" , "Pat's tiff with the judge" , "One authorised" , "Court official" .)