When did a Racer, which is what it was always known as when I was a kid, become a Road Bike? Was it because of the emergence of the Mountain Bike and so some further distinction was thought necessary?
Hybrid makes sense to me. As do Fixed, Singlespeed, Folder, Recumbent (only the name makes sense there, obviously), BMX and so on...
But Road bike doesn't truly define it does it? The rest can go on the road as well. I'm going back to using Racer. In much the same way that I refer to a seatpost as a seatpin. Call me old-fashioned if you like... :P