What is the apparent arch, or vault, of heaven, which in a clear day is of a blue color; the heavens; the firmament; -- sometimes in the plural. The Norweyan banners flout the sky. Shak called?

sky — The apparent arch, or vault, of heaven, which in a clear day is of a blue color; the heavens; the firmament; -- sometimes in the plural. The Norweyan banners flout the sky. Shak. (Webster's 1913.)

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