- a galaxy that emits much more strongly in the radio part of the spectrum than does a typical galaxy.
- a galaxy that is a strong emitter of radio waves
- A galaxy that emits large amounts of radio energy. Radio galaxies are typically elliptical galaxies with large symmetrical lobes. The centers of radio galaxies are active galactic nuclei, and many expel one or more jets of matter directly from the nucleus that can be observed in the visible spectrum and extend for millions of light-years. See also Seyfert galaxy.