American employer cleaned out client (4)
I believe the answer is:
user
'client' is the definition.
(I've seen this in another clue)
'american employer cleaned out' is the wordplay.
'american' becomes 'us' (abbreviation for United States).
'cleaned out' suggests removing the centre.
'employer' with its centre taken out is 'er'.
'us'+'er'='USER'
(Other definitions for user that I've seen before include "Someone who exploits another" , "Junkie's" , "Manipulative woman" , "Maybe one needing pot" , "Consumer" .)