Employ again (5)
I believe the answer is:
reuse
'employ again' is the definition.
('use' can be a synonym for 'employ' so perhaps 'reuse' is OK for 'employ again')
This is the entire clue.
(Other definitions for reuse that I've seen before include "Employ again" , "Recycle (something)" , "The aim of recycling" , "For another time enjoy" .)