It's not a wheel, it's a ...

That’s what she said.

I like sansaxle, personally, but I think that should somehow apply to what looks like a traditional four (or more) wheel vehicle configuration that doesn’t use axles as we currently define them. If you really don’t like “roller” then maybe “Roll-O-Matic” works.

It’s axis of rotation is longer than it’s diameter I’d have to say.

Well said, HD. See #20.

Roll-O-Matic sounds like Ron Popeil should be selling it on TV!

How about just “cylinder”?

A shape that is not circular, but which can still be used smoothly as a roller.