Definition of: sky

(skī) noun plural skies
1. The blue vault, or a part of it, that seems to bend over the earth; the firmament.
2. The upper atmosphere; especially, the region of the clouds.
3. The celestial regions or powers; heaven.
4. Climate; weather.
5. Obs. A cloud.
—v.t. skied, sky·ing Colloq. In games, to bat or throw (a ball) high into the air. [<ON sk cloud]