polo

Any field or arena dedicated to the regular play of polo may claim it as a usage. This is restricted to versions of the game played on horseback or on other animals (such as elephants), and does not include space for such games as bicycle polo, Segway polo, or water polo.

Regular play of mounted polo is the defining use. A field or arena can serve it, and the definition expressly includes play on animals other than horses.

Bicycle polo and Segway polo use vehicles instead of animals, while water polo is played in water. The shared word polo does not bring those activities within this mounted-sport definition.