Horse tail, horsetail or horse's tail may refer to: *the

tail The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ...

of a horse *

Equisetidae Equisetidae is one of the four subclasses of Polypodiopsida (ferns), a group of vascular plants with a fossil record going back to the Devonian. They are commonly known as horsetails. They typically grow in wet areas, with whorls of needle-like ...

, a subclass of living and extinct plants known as horsetails **

Equisetales Equisetales is an order of subclass Equisetidae with only one living family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relation ...

, the single extant order of Equisetidae ***

Equisetaceae Equisetaceae, also known as the horsetail family, is a family of ferns and the only surviving family of the order Equisetales, with one surviving genus, ''Equisetum'', comprising about twenty species. Evolution and systematics Equisetaceae is ...

, the horsetail family, the only extant family of Equisetales ****''

Equisetum ''Equisetum'' (; horsetail) is the only living genus in Equisetaceae, a family of vascular plants that reproduce by spores rather than seeds. ''Equisetum'' is a "living fossil", the only living genus of the entire subclass Equisetidae, which ...

'', horsetail, the only living genus in Equisetaceae *

Cauda equina The cauda equina () is a bundle of spinal nerves and spinal nerve rootlets, consisting of the second through fifth lumbar nerve pairs, the first through fifth sacral nerve pairs, and the coccygeal nerve, all of which arise from the lumbar enl ...

('horse's tail'), a bundle of spinal nerves and spinal nerve rootlets in humans * a type of

waterfall A waterfall is any point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf. Waterfalls can be formed in seve ...

See also