Dishonest antivirus software which tricks users into buying or installing it, usually by infecting a user's computer, or by pretending the computer is infected.
Additional Details
Winantivirus is an rogue antivirus program that pretends to scan the system, and then displays false or exaggerated results.
Here is a sample screenshot of program while it performs a system scan:
This rogueware is closely related to the XPAntivirus rogueware family.