Is there a difference between these two terms?

Technically speaking, yes. Common language speaking, no. 

OEM Wheels and OEM Rims are referred to as the same product, majority of the time- there is with one slight difference. 

Majority of customers and vendors use these terms interchangeably (we do too). However, technically speaking - the rim is a part of the wheel.

A wheel is an entire object that occupies the space within the rubber tire. This view displays the full body of the wheel. 

A rim is the outside/noticeable a part of the wheel which is facing outward, after a wheel installation. This view displays the front of the wheel, which is considered the rim.

In conclusion, these terms are used interchangeably every day! If people want to get technical, you now possess the knowledge of the real difference.

Thanks for reading!