A type of stadium where the roof can be moved into place when necessary, then pulled back when not necessary. This allows the benefits of an open-air stadium, like a natural grass field and sunlight, but keeps out annoying things like rain and stifling heat when such things would interfere with the game being played, or fans' enjoyment thereof.

The first such stadium was SkyDome in Toronto. The ranks now include Bank One Ballpark in Phoenix, Safeco Field in Seattle, and Enron Field in Houston.