- a horse's tail
- any of the only surviving genus (Equisetum) of a division (Equisetophyta) of plants having hollow, jointed stems, with scalelike leaves at the joints and spores borne in terminal cones; scouring rush
See horsetail in American Heritage Dictionary 4
Any of various nonflowering plants of the genus Equisetum, having a jointed hollow stem and narrow, sometimes much reduced leaves. Also called equisetum.
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