Writer is flipping working for retirement fund (7)
I believe the answer is:
pension
'retirement fund' is the definition.
(I've seen this in another clue)
'writer is flipping working' is the wordplay.
'writer' becomes 'pen' (something which writes).
'flipping' is a reversal indicator.
'working' becomes 'on' (on can mean working or activated).
'is' backwards is 'si'.
'pen'+'si'+'on'='PENSION'
'for' acts as a link.
(Other definitions for pension that I've seen before include "Bed and breakfast or small hotel in France" , "Nice little hotel" , "Payment to retired persons a continental boarding house" , "residence abroad" , "Payment to traitor" .)