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[mairz-teyl] /ˈmɛərzˌteɪl/
a long narrow cirrus cloud whose flowing appearance somewhat resembles a horse's tail.
an erect, aquatic, Old World plant, Hippuris vulgaris, having crowded whorls of narrow, hairlike leaves.
1755-65 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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British Dictionary definitions for mare's-tail


a wisp of trailing cirrus cloud, often indicating high winds in the upper troposphere
an erect cosmopolitan pond plant, Hippuris vulgaris, with minute flowers and crowded whorls of narrow leaves: family Hippuridaceae
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Encyclopedia Article for mare's-tail

the aquatic plant Hippuris vulgaris or either of two other species of its genus, in the plantain family (Plantaginaceae). Mare's-tail grows from submerged, stout rootstocks along the margins of lakes and ponds in temperate regions throughout the world. It resembles the unrelated horsetail (Equisetum species) in having whorls of small, linear leaves at intervals along the stem. The stems rise about 30 cm (12 inches) above the water to produce, in the upper angles between the stems and leaves, highly reduced, tiny, greenish, wind-pollinated bisexual flowers, each consisting of one male pollen-producing stamen and one female ovary with a single ovule. Mare's-tail plants are sometimes grown in bog or pond gardens.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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