mare's tail

plural mare's tails or mares' tails

Definition of mare's tail

1a : a common aquatic plant (Hippuris vulgaris of the family Hippuridaceae) with elongated shoots having dense whorls of narrow finely tapered leaves
2 : a cirrus cloud that has a long slender flowing appearance

First Known Use of mare's tail

15th century, in the meaning defined at sense 1a

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The first known use of mare's tail was in the 15th century

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Cite this Entry

“Mare's tail.” Dictionary, Merriam-Webster, Accessed 23 Sep. 2020.

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