Bogus offer (4)
I believe the answer is:
scam
'bogus offer' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for scam that I've seen before include "Fraudulent scheme, swindle" , "Hoax" , "Swindle (Slang)" , "Confidence trick, swindle" , "A slangy swindle or fraud" .)