Fraudulent business scheme (4)
I believe the answer is:
scam
'fraudulent business scheme' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for scam that I've seen before include "Fraud, trick (slang)" , "Swindle (sl.)" , "An informal swindle" , "A modern kind of swindle" , "Rip-off" .)