Is a motorcycle still a motorcycle if it has four wheels?

Is a motorcycle still a motorcycle if it has four wheels?

The 2010 Cosmos 4RW V8 Muscle Bike is one crazy-looking motorcycle, but I can't help but think it's not technically a motorcycle. I mean, it has four wheels, albeit very close together. I don't think it'd be possible for it to just fall on its side.

In any case, it looks pretty serious. Those 17-inch wheels support a 350 cubic inch engine that's got 350 horsepower. If you want one, it'll cost you: $93,200, to be exact.