Large groups of galaxy clusters that appear in sheetlike and threadlike shapes are known as?

Large groups of galaxy clusters that appear in sheetlike and threadlike shapes are known as superclusters. These are a cluster of galaxies which themselves occur as clusters as well. One example is the Virgo supercluster. It is a mass concentration of galaxies that contains the Virgo Cluster.

Its in the national history museum and you can't se the original because its locked away in a vault