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radio source

noun Astronomy.
  1. a cosmic object or phenomenon, as a galaxy, pulsar, quasar, or the remnant of a supernova or of a galactic collision, that emits radio waves.

Origin of radio source

First recorded in 1945–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for radio source

radio source

noun
  1. a celestial object, such as a supernova remnant or quasar, that is a source of radio waves
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012