horsetail

American  

[hawrs-teyl] / ˈhɔrsˌteɪl /

noun

1. Also called scouring rush.  any nonflowering plant of the genus Equisetum, having hollow, jointed stems.

2. a horse's tail formerly used as a Turkish military standard or as an ensign of a pasha, the number of tails increasing with the rank.

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horsetail British  

/ ˈhɔːsˌteɪl /

noun

1. any tracheophyte plant of the genus Equisetum , having jointed stems with whorls of small dark toothlike leaves and producing spores within conelike structures at the tips of the stems: phylum Sphenophyta

2. a stylized horse's tail formerly used as the emblem of a pasha, the number of tails increasing with rank

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horsetail Scientific  

/ hôrs′tāl′ /

1. A member of a genus, Equisetum, of seedless vascular plants having a jointed hollow stem and narrow, sometimes much reduced leaves. Plants extremely similar to modern horsetails are known from fossils 300 million years old. The horsetails are the last surviving members of the phylum Sphenophyta, which dominated the forests of the Devonian and Carboniferous periods.

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Etymology

Origin of horsetail

First recorded in 1350–1400, horsetail is from Middle English horse tayle. See horse, tail ¹

Example Sentences

The Yosemite National Park website includes a detailed map of the Horsetail Fall viewing area and restrictions.

From Los Angeles Times • Jan. 15, 2026

Yosemite officials are starting up reservations for February weekends at Horsetail Fall in the hope of curtailing damage to surrounding areas by visitors.

From Los Angeles Times • Feb. 5, 2025

Even those not visiting Horsetail Fall on the dates listed above are required to apply for a reservation.

From Los Angeles Times • Feb. 5, 2025

Should the sunset properly backlight a small waterfall known as Horsetail Fall just so, the cascading water becomes a “firefall,” taking on an orange glow that can appear very lava-like.

From Los Angeles Times • Nov. 14, 2024

Upper part of a stem of a Horsetail, Equisetum sylvaticum.

From The Elements of Botany For Beginners and For Schools by Gray, Asa