Fire pocket (4)
I believe the answer is:
sack
This clue is a double definition.
'fire' is the first definition.
(dismiss someone from their job)
'pocket' is the second definition.
(I know that pocket can be written as sack)
(Other definitions for sack that I've seen before include "Large hessian bag" , "Fire; hessian bag" , "Fire the old drink?" , "Large canvas bag" , "Container for coal etc" .)