(astronomy) An icy planetoid: an astronomical object, such as Pluto, Sedna or (for some authors) Ceres that is large enough to be a world and contains more ice than a typical asteroid.

(astronomy) A dying star of low or medium mass, more solid and dense but less bright than the sun.

(astronomy) A small, relatively cool star of the main sequence; most stars in the Milky Way are red dwarfs.

plural of brown dwarf

(astronomy) A starlike object that contracts to about the volume of the planet Jupiter after its formation phase; its mass may range from several times that of Jupiter, such that it fuses deuterium, up to just below the threshold of sustained hydrogen fusion.

(astronomy) A hypothesized white dwarf that has cooled down and no longer emits visible light.

(astronomy) A world-like planetoid of the Solar system, that is smaller than the classical planets. More specifically, any astronomical body which has a geology defined by hydrostatic equilibrium (and thus has taken the shape a body of water would take, as opposed to a small Solar System body), orbits the Sun (as opposed to a moon), and does not gravitationally dominate other bodies near its orbit (as opposed to a classical planet or, in IAU usage, as opposed to a planet).

(astronomy) A dwarf spheroidal galaxy

A "sport" in which contestants compete to throw a small person the farthest.

(astronomy) Any galaxy, considerably smaller than the Milky Way, that has only several billions of stars.