Employed in Chartreuse daily (4)
I believe the answer is:
used
'employed' is the definition.
('use' can be a synonym of 'employ')
'in chartreuse daily' is the wordplay.
'in' indicates the answer is hidden within the clue.
'USED' is hidden in the letters of 'chartreuse daily'.
(Other definitions for used that I've seen before include "like majority of cars?" , "Second-hand; exploited" , "Scottish expert" , "not got directly" , "Accustomed - exploited" .)