(astronomy) Any of a class of galaxies that have nuclei with excessive amounts of ultraviolet emissions.

(galaxies) a type of galaxy created by ram pressure stripping the interstellar gas from a galaxy by the high temperature higher pressure intracluster medium, forming long tendrils of concentrated gas trailing behind the galaxy, which form nebulae and new stars, giving the appearance of celestial jellyfish

(cosmology) A massive, thread-like formation of gravitationally bound galaxies forming the boundaries between large voids in the universe.

plural of galaxy filament

(astronomy) A galaxy having a number of arms of younger stars that spiral out from the centre containing older ones

A galaxy having a smooth, featureless light-profile. It is one of the three main classes of galaxies originally described by Edwin Hubble in his 1936 work “The Realm of the Nebulae”.

(astronomy) Type of galaxy that is very luminous at radio wavelengths.

(astronomy) A spiral galaxy in the Local Group and closest to the Milky Way, visible to the naked eye in the constellation of Andromeda, the brightest of the Messier objects and often referred to by its designation M31.

(astronomy, galaxies) A cluster of hundreds of galaxies.

(astronomy, galaxies) plural of galaxy cluster