Technically, the term “wheel” refers to the whole assembly that includes the hub, spokes, and rim, while ‘rim’ is just a part of the wheel. It’s the outer edge of the wheel that holds the tire in place. So, when you’re talking about the whole thing— the part that spins and to which the tire attaches—that’s the wheel. But if you’re referring to just the outer circular design of the metal that cradles the tire—that’s the rim. But you might hear these terms used interchangeably.