Guard retreat following conflict (6)
I believe the answer is:
warden
'guard' is the definition.
(I've seen this before)
'retreat following conflict' is the wordplay.
'retreat' becomes 'den' (both can mean a lair or hideout).
'following' is a charade indicator (letters next to each other).
'conflict' becomes 'war' (war is a kind of conflict).
'den' after 'war' is 'WARDEN'.
(Other definitions for warden that I've seen before include "Guardian" , "Custodian" , "Official with supervisory duties, as in relation to a church" , "Caretaker" , "Guard, keeper" .)