What is a long streaky cloud, spreading out like a horse's tail, and believed to indicate rain; a cirrus cloud. See Cloud. Mackerel sky and mare's-tails Make tall ships carry low sails. Old Rhyme called?

mareschal — A long streaky cloud, spreading out like a horse's tail, and believed to indicate rain; a cirrus cloud. See Cloud. Mackerel sky and mare's-tails Make tall ships carry low sails. Old Rhyme. (Webster's 1913.)

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