Sharp chopper -- ace cut (6)
I believe the answer is:
clever
'sharp' is the definition.
(I've seen this before)
'chopper ace cut' is the wordplay.
'chopper' becomes 'cleaver' (a cleaver chops things).
'ace' becomes 'a'.
'cut' is a deletion indicator.
'cleaver' with 'a' removed is 'CLEVER'.
(Other definitions for clever that I've seen before include "Mentally or physically skilful" , "Quick at learning and understanding" , "brilliant" , "Box ---, outwit someone" , "Quick at learning, bright" .)