Allow me to get on my soap box for a minute.

This morning I went through the drive thou at McDonalds and ordered an iced coffee. Now the sign had two prices. I made the mistake of asking for a small iced coffee, the person taking my order asked if a medium would be okay. I said sure looking again at the sign to see if I missed the third price. No, not a third price on the board. When I reached the window I asked if they had three sizes and she said, "No just medium and large." Now correct me if I'm wrong but don't you have to have a small and large to have a medium.

When I got to work I looked up medium in the dictionary, in this context the definition says:
Something in a middle position.