Employed; second hand (4)
I believe the answer is:
used
I believe this clue is a double definition.
'employed' is the first definition.
('use' can be a synonym of 'employ')
'second hand' is the second definition.
(second hand can mean previously owned or used)
(Other definitions for used that I've seen before include "Brought into service" , "Enjoyed" , "Not fresh" , "taken advantage of!" , "Accustomed, having been put into service" .)