Hi MaryPhares - A spacer is device that you attach to your inhaler that helps improve the delivery of the medication. They come in a variety of shapes and sizes, but generally are tubular in shape. At one end you attach your inhaler and the other end is the mouthpiece.
There are a couple of advantages to using them. For one thing, they "hold" the medication in the chamber so that you don't have to worry as much about coordinating your breath with actuating the inhaler. It also is helpful in making sure the medication get's into your airways instead of just the back of your mouth.
Regards,
Lyn (site moderator)