Merriam-Webster's Collegiate® Dictionary, 11th Edition
SKY
I. noun (plural skies)
Etymology: Middle English, cloud, sky, from Old Norse skȳ cloud; akin to Old English scēo cloud
Date: 13th century
the upper atmosphere or expanse of space that constitutes an apparent great vault or arch over the earth, heaven 2,
3. weather in the upper atmosphere, climate ,
II. verb (skied or skyed; skying)
Date: 1802
transitive verb to throw or toss up ; flip , to hang (as a painting) above the line of vision, to hit (a ball) high into the air, intransitive verb to jump high