cD galaxySee clusters of galaxies; galaxies.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006
CD galaxy[¦sē¦dē ′gal·ik·sē]
A supergiant elliptical galaxy with an extended envelope, the largest known type of galaxy.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.