elliptical galaxyelliptical galaxyn. A galaxy with an elliptical shape, containing relatively little gas and dust and having older stellar populations as compared to spiral galaxies.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.ellip?tical gal?axy n. a galaxy having an elliptical shape. Compare spiral galaxy. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.