Sly, crafty (7)
I believe the answer is:
cunning
I believe this is a double definition.
'sly' is the first definition.
(I know that sly can be written as cunning)
'crafty' is the second definition.
(I know that crafty can be written as cunning)
(Other definitions for cunning that I've seen before include "Clever, ingenious" , "Artful" , "Devious" , "Sly" , "'Craftiness, guile (7)'" .)