mare’s-tail

mare’s-tail [mairz-teyl] Word Origin noun

1. a long narrow cirrus cloud whose flowing appearance somewhat resembles a horse’s tail.
2. an erect, aquatic, Old World plant, Hippuris vulgaris, having crowded whorls of narrow, hairlike leaves.

Origin of mare’s-tail First recorded in 1755–65 British Dictionary definitions for mare’s-tail mare’s-tail noun

1. a wisp of trailing cirrus cloud, often indicating high winds in the upper troposphere
2. an erect cosmopolitan pond plant, Hippuris vulgaris, with minute flowers and crowded whorls of narrow leaves: family Hippuridaceae