D defs.my
Entry 2 senses Webster, 1913

Mare's-tail

· Mare'sĀ·-tail · IPA
01 n. A long streaky cloud, spreading out like a horse's tail, and believed to indicate rain; a cirrus cloud. See Cloud.
  1. 1.
    A long streaky cloud, spreading out like a horse's tail, and believed to indicate rain; a cirrus cloud. See Cloud. See: Cloud
    “Mackerel sky and mare's-tails Make tall ships carry low sails.” — Old Rhyme.
  2. 2.
    An aquatic plant of the genus Hippuris (Hippuris vulgaris), having narrow leaves in whorls.(Bot.)