Do study (3)

I believe the answer is:
con
I believe this is a double definition.
'do' is the first definition.
'study' is the second definition.
(I've seen this before)
(Other definitions for con that I've seen before include "Prisoner (sl.)" , "Learn; swindle" , "Peruse carefully or swindle" , "Deception; disadvantage" , "Study - swindle" .)