Car With Rims

The terms "wheel" and "rim" are often used synonymously, as in decorative wheels being called rims. Some authors are careful to use "rim" for only the outer portion of a wheel, where the tire mounts, just as the rim of a coffee cup or a meteor crater does not refer to the entire object. Others use "rim" to mean the entire metal part to which the tire mounts, because the rim and the wheel are often cast or stamped from a single piece of metal instead of being distinct as with wire wheels. At the same time, "wheel" may refer to the entire rotating assembly, including the tire.
Railroad usage
In railroad usage the conical running surface of the wheels may be called a rim or a tyre.