#extragalactic_nebula__extragalacticnebula__galaxy  (astronomy) a collection of star systems; any of the billions of systems each having many stars and nebulae and dust; "`extragalactic nebula' is a former name for `galaxy'"
  supertype:  #aggregation__collection__accumulation__assemblage  several things grouped together
  instance:  #Milky_Way_Galaxy
  member:  #star
  substance:  #cosmic_dust
  member of:  #universe
  subtype:  #spiral_galaxy__spiral_nebula  a galaxy having a spiral structure; arms containing younger stars spiral out from old stars at the center
  subtype:  #Great_Attractor  a massive grouping of galaxies in the direction of Centaurus and Hydra whose gravitational attraction is believed to cause deviations in the paths of other galaxies
  subtype:  #Magellanic_Cloud  either of two small galaxies orbiting the Milky Way; visible near the south celestial pole
     instance:  #Large_Magellanic_Cloud  #Small_Magellanic_Cloud

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