Welkin
Welkin , noun
[Old English welken, welkene, welkne, wolcne, weolcne, Anglo-Saxon wolcen, pl. wolcnu, a cloud; akin to Dutch wolk, OFries. wolken, Old Saxon wolkan, German wolke, Old High German wolchan, and probably to German welk withered, Old High German welc moist, Russ. & OSlav. vlaga moisture, Lithuanian vilgyti to moisten.]
The visible regions of the air; the vault of heaven; the sky.
On the welkne shoon the sterres lyght.
The fair welkin foully overcast.
When storms the welkin rend.
Used adjectively by Shakespeare in the phase, “Your welkin eye,” with uncertain meaning.