Centaur

The name Centaur traditionally refers to a race of mythological Earth creatures with the upper body of a human being attached to the body of a horse. Females of this species are sometimes called Centaurides.

In astronomy
In astronomy, the word is also used to refer to a category of minor planets with features of both comets and asteroids. Additionally, the constellation of Centaurus is named after this race, and notably includes the Alpha Centauri System - the closest galactic neighbor of the Sol System - as well as countless others. There is also a galaxy known as Centaurus A, which belongs to the same group as the M83 Galaxy, which in turn makes up part of the Virgo Supercluster. Finally, there is also a galactic cluster known as the Centaurus Cluster, which makes up part of the Hydra-Centaurus Supercluster.

Species named "Centaurs"
For the reasons listed above, the words "Centaur", "Centauri" or "Centaurian" are commonly applied to alien species which more often than not share no physical similarities with the mythical Centaurs, but hail from one of the above-mentioned astronomical locations which are themselves named after the race. These include:
 * Centaurs from Futurama, which resemble their mythical brethren.
 * Centaurs from Factoring Humanity, a race of winged insectoids.
 * Centaurs from Voyage to the Bottom of the Sea, a race of humanoids with features resembling both amphibians and arthropods.
 * Centauri from Babylon 5, a humanoid species.
 * Alpha Centaurans from Doctor Who, a race of cyclopic gastropods.