Fringe benefit, for short (4)
I believe the answer is:
perk
'fringe benefit for short' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for perk that I've seen before include "Employee's benefit as an entitlement of job" , "Company car, for example" , "Incidental benefit from one's employment" , "Incidental gain" , "Informal goodie given on top of salary" .)