mare's tail


plural mare's tails or mares' tails
: a common aquatic plant (Hippuris vulgaris of the family Hippuridaceae) with elongated shoots having dense whorls of narrow finely tapered leaves
: a cirrus cloud that has a long slender flowing appearance

Word History

First Known Use

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

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

Dictionary Entries Near mare's tail

Cite this Entry

“Mare's tail.” Dictionary, Merriam-Webster, Accessed 30 May. 2024.

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